Detection of Anions questions

Chemical analysis has played a major role in all of the following, except ..........

1. A diagnosing and treating diseases.
2. B determining the suitability of iron ores.
3. C improving soil and crop properties.
4. D the suitable conditions for the reaction of iron oxides with acids.

When a solution of compound (A) is added to a solution of compound (Y), a reddish-brown precipitate of compound (W) forms.
Which of the following is correct?

1. A (W) : FeCl , qualitative chemical analysis.
2. B (W) : FeCl , quantitative chemical analysis.
3. C (W) : Fe(OH)₃ , qualitative chemical analysis.
4. D (W) : Fe(OH)₃ , quantitative chemical analysis.

All of the following describe analytical chemistry, except ............

1. A Analytical chemistry is closely linked to industry.
2. B One of the tasks of analytical chemistry is determining the chemical formula of an unknown compound.
3. C Quantitative analysis is carried out before qualitative analysis.
4. D One of the tasks of quantitative analysis is determining the percentages of elements in alloys.

Analytical chemistry is linked to many other branches of science, such as ..........

1. A physics and biology only.
2. B geology and mineralogy only.
3. C physics and mineralogy only.
4. D physics, biology, geology and mineralogy.

A pure sample of Na₂CO₃ can be identified through ..........

1. A its solubility in water.
2. B its physical state.
3. C its melting and boiling points.
4. D its reaction with HCl(aq)

Qualitative analysis aims at all of the following, except ..........

1. A proving whether the unknown sample is organic or inorganic.
2. B identifying the elements or ions present in the unknown sample.
3. C determining the concentration of the compound that makes up the unknown sample.
4. D identifying the functional groups present in the unknown sample.

All carbonate and bicarbonate salts agree in all of the following, except ..........

1. A the acid they are derived from.
2. B their solubility in water.
3. C their reaction with acids.
4. D their reaction with MgSO₄(aq)

Turbidity forms when mixing solutions of ..........

1. A ammonia and sodium chloride.
2. B copper(II) sulphate and magnesium chloride.
3. C zinc nitrate and ammonium carbonate.
4. D sodium hydroxide and potassium iodide.

The solution of the substance that must be added to a solution containing Mg²⁺ ions to separate them as a precipitate in the cold is ..........

1. A NaHCO₃
2. B K₂SO₄
3. C Na₂CO₃
4. D KNO₃

A precipitate forms when mixing solutions of ............

1. A H₂SO₄ , CuCl₂
2. B CuCl₂ , Na₂CO₃
3. C KCl , H₂SO₄
4. D NaCl , HNO₃

The anion of the salt formed by passing carbon dioxide gas through clear limewater for a long time can be detected using ..........

1. A magnesium sulphate solution in the cold.
2. B sodium hydroxide solution.
3. C magnesium sulphate solution, then heating.
4. D potassium dichromate.

HCl(aq) is used to distinguish between the following pairs of salts, except ............

1. A Na₂S , NaNO₃
2. B Na₂SO₃ , NaBr
3. C NaNO₂ , Na₂SO₄
4. D NaI , Na₃PO₄

A beaker contains MgCO₃ and Mg(HCO₃)₂; an amount of water was added to them with stirring.
Which of the following is needed to increase the mass of the precipitated substance?

1. A Adding HNO₃(aq)
2. B Adding more water.
3. C Heating.
4. D Adding H₂SO₄(aq)

When a solution of salt (X) reacts with a solution of salt (Y), a white precipitate forms only after heating.
What is the anion of salt (X) and the cation of salt (Y)?

1. A (X) : CO₃²⁻ , (Y) : Na⁺
2. B (X) : S²⁻ , (Y) : Ag⁺
3. C (X) : HCO₃⁻ , (Y) : Mg²⁺
4. D (X) : SO₄²⁻ , (Y) : Ca²⁺

A solid mixture of the salts sodium bicarbonate, sodium sulphate and sodium nitrate.
What gas (gases) is formed when dilute HI acid is added to it?

1. A CO₂ only.
2. B NO₂ only.
3. C CO₂ , NO₂ only.
4. D CO₂ , NO₂ , SO₂

MgCO₃(s) and Mg(HCO₃)₂(s) can be distinguished in the laboratory using ............

1. A HCl(aq)
2. B H₂O(l)
3. C HNO₃(aq)
4. D Na₂SO₄(aq)

A mixture contains the two anions CO₃²⁻(aq) and SO₄²⁻(aq).
Which of the following, when added to the mixture, precipitates one of the two anions?

1. A NaNO₃(aq)
2. B NH₄NO₂(s)
3. C FeCl₃(aq)
4. D K₂SO₃(s)

For which pair of the following anions is HNO₃(aq) not used to distinguish between them?

1. A CO₃²⁻ , NO₂⁻
2. B SO₃²⁻ , S₂O₃²⁻
3. C CO₃²⁻ , HCO₃⁻
4. D S²⁻ , NO₂⁻

From the opposite chart:
Mixture (X) is made of the two anions ..........

1. A NO₃⁻ , CO₃²⁻
2. B HCO₃⁻ , CO₃²⁻
3. C NO₃⁻ , SO₃²⁻
4. D Cl⁻ , SO₃²⁻

When lead(II) nitrate solution is added to solution (X), a white precipitate forms, and when drops of dilute nitric acid
are added to the white precipitate, effervescence is observed and the precipitate disappears. Solution (X) is ..........

1. A zinc chloride.
2. B ammonium iodide.
3. C aluminium sulphate.
4. D sodium carbonate.

Compound (X) has the following properties:
• 1 mol of it dissolves in water forming 3 mol of ions.
• It reacts with ammonium carbonate forming an acidic gas.
Compound (X) is ............

1. A calcium hydroxide.
2. B nitric acid.
3. C sodium hydroxide.
4. D sulphuric acid.

From the opposite chart:
Which of the following is correct?

1. A (A) : Na₂CO₃ , (B) : NaHCO₃ , (C) : H₂O , (D) : CaCO₃
2. B (A) : NaHCO₃ , (B) : Na₂O , (C) : H₂O , (D) : Ca(HCO₃)₂
3. C (A) : NaHCO₃ , (B) : Na₂CO₃ , (C) : CO₂ , (D) : CaCO₃
4. D (A) : KHCO₃ , (B) : K₂CO₃ , (C) : CO₂ , (D) : Ca(HCO₃)₂

When gas (A) is passed through clear limewater for a short time a white precipitate forms, and when the same gas is passed over heated charcoal
gas (B) forms. Gases (A) and (B) are ..........

1. A (A) : CO₂ , (B) : CO
2. B (A) : CO , (B) : CO₂
3. C (A) : CO₂ , (B) : CO₂
4. D (A) : CO , (B) : CO

Sodium carbonate and sodium chloride can be distinguished using ..........

1. A dilute nitric acid.
2. B potassium sulphite.
3. C ammonium hydroxide solution.
4. D potassium nitrate solution.

The oxidation numbers of chromium in the compound used in making dyes and in the compound formed by the reaction of sulphur dioxide gas
with potassium dichromate solution acidified with conc. sulphuric acid are ............

1. A +3 , +6
2. B +3 , +3
3. C +4 , +4
4. D +4 , +6

Which of the following graphs represents the mass of a mixture of sodium carbonate and excess dilute hydrochloric acid
in an open beaker over time?

1. A Graph (A)
2. B Graph (B)
3. C Graph (C)
4. D Graph (D)

Strongly heating a sample of substance (A) gives a red solid (B) and a colourless gas (C) that turns a paper moistened
with acidified potassium dichromate solution green.
Which of the following is correct?

1. A (A) : Fe₂(SO₄)₃ , (B) : FeO , (C) : SO₂
2. B (A) : FeSO₄ , (B) : Fe₂O₃ , (C) : SO₂
3. C (A) : Fe₂(SO₄)₃ , (B) : Fe₂O₃ , (C) : SO₃
4. D (A) : FeSO₄ , (B) : FeO , (C) : SO₃

When salt (X) is strongly heated, two sulphur compounds form, and when potassium permanganate solution acidified
with conc. sulphuric acid is added to a solution of salt (Y), two sulphate salts form.
Which of the following is correct?

1. A (X) : FeSO₄ , (Y) : NaNO₃
2. B (X) : CuSO₄ , (Y) : NaNO₂
3. C (X) : CuSO₄ , (Y) : NaNO₃
4. D (X) : FeSO₄ , (Y) : NaNO₂

When compound (A) is dissolved in:
• dilute hydrochloric acid, colourless gas (B) is given off.
• water, and then silver nitrate solution is added, a white precipitate (C) forms.
Which of the following gives compound (A), gas (B) and the effect of heating precipitate (C)?

1. A (A) : Na₂SO₄ , (B) : SO₃ , (C) : turns black.
2. B (A) : Na₂SO₃ , (B) : SO₂ , (C) : the precipitate disappears.
3. C (A) : Na₂S , (B) : H₂S , (C) : the precipitate disappears.
4. D (A) : Na₂SO₃ , (B) : SO₂ , (C) : turns black.

Which of the following is used to distinguish between sulphur dioxide gas and carbon dioxide gas?

1. A Acidified potassium dichromate solution.
2. B Sodium hydroxide solution.
3. C Sodium carbonate solution.
4. D A blue litmus paper moistened with water.

From the following equation:
2KMnO₄(aq) + 5SO₂(g) + 2H₂O(l) ⟶ 2H₂SO₄(aq) + K₂SO₄(aq) + 2MnSO₄(aq)
All of the following are correct, except ..........

1. A The mixture of reaction products contains a paramagnetic substance.
2. B Acidified potassium permanganate solution is used as a reagent for SO₂ gas.
3. C SO₂ gas acts as the reducing agent.
4. D Oxidation of the manganese ion takes place.

From the following ionic equation:
3SO₃²⁻(aq) + Cr₂O₇²⁻(aq) + 8H⁺(aq) ⟶ 3SO₄²⁻(aq) + 2Cr³⁺(aq) + 4H₂O(l)
All of the following are correct, except ..........

1. A The colour of the solution changes from orange to green.
2. B The SO₃²⁻ anion acts as the reducing agent.
3. C The H⁺ ions come from conc. sulphuric acid.
4. D The oxidation state of chromium changes from +3 to +6

The following table shows the properties of the two gases (X) and (Y):
• Properties of gas (X): can be oxidised, has a pungent smell, decolourises acidified KMnO₄ solution.
• Properties of gas (Y): can be reduced, odourless, forms a white precipitate when passed through Ca(OH)₂ solution.
Which of the following is correct?

1. A (X) : SO₂ , (Y) : CO₂
2. B (X) : SO₃ , (Y) : CO
3. C (X) : SO₂ , (Y) : CO
4. D (X) : SO₃ , (Y) : CO₂

Which of the following anions forms a black water-insoluble substance with the cation (X⁺) whose electron configuration ends
with the sublevel (4d¹⁰)?

1. A SO₃²⁻
2. B S²⁻
3. C NO₃⁻
4. D HCO₃⁻

According to the products of the two opposite reactions:
• anion (X) + HCl(aq) ⟶ colourless gas (Y) with a bad smell
• gas (Y) + (CH₃COO)₂Pb(aq) ⟶ a black solid
Which of the following is correct?

1. A (X) : S²⁻ , (Y) : SO₂
2. B (X) : Cl⁻ , (Y) : HCl
3. C (X) : S²⁻ , (Y) : H₂S
4. D (X) : SO₃²⁻ , (Y) : H₂S

When gas (1) is passed through solution (2), no colour change occurs.
Which of the following gives gas (1) and solution (2)?

1. A (1) : CO₂ , (2) : Ca(OH)₂
2. B (1) : SO₂ , (2) : K₂Cr₂O₇ / H⁺
3. C (1) : H₂S , (2) : (CH₃COO)₂Pb
4. D (1) : NH₃ , (2) : NaOH

For which pairs of the following anions does each one alone form the same gas when treated with a suitable acid?

1. A The pair (CO₃²⁻ , HCO₃⁻) : correct , the pair (SO₃²⁻ , S₂O₃²⁻) : correct
2. B The pair (CO₃²⁻ , HCO₃⁻) : wrong , the pair (SO₃²⁻ , S₂O₃²⁻) : correct
3. C The pair (CO₃²⁻ , HCO₃⁻) : correct , the pair (SO₃²⁻ , S₂O₃²⁻) : wrong
4. D The pair (CO₃²⁻ , HCO₃⁻) : wrong , the pair (SO₃²⁻ , S₂O₃²⁻) : wrong

A solid compound reacts with H₂SO₄(aq) and the gaseous compound (X) forms, whose anion is oxidised forming one of the impurities of iron ores.
All of the following are correct, except ..........

1. A Compound (X) forms a precipitate with (Pb²⁺).
2. B The anion of compound (X) forms a black precipitate with (Ag⁺).
3. C The oxidation number of the anion of gas (X) equals (+4).
4. D The aqueous solution of gas (X) is more volatile than HNO₃(aq)

Dilute sulphuric acid was added to a salt, and a gas was given off that turns a paper moistened with acidified K₂Cr₂O₇ solution green,
in addition to the formation of a yellow suspension. The anion of this salt is ..........

1. A sulphide.
2. B sulphite.
3. C thiosulphate.
4. D sulphate.

When dilute hydrochloric acid is added to sodium thiosulphate salt, ............ takes place.

1. A oxidation of sulphur and reduction of oxygen
2. B reduction of sulphur and oxidation of oxygen
3. C oxidation and reduction of oxygen
4. D oxidation and reduction of sulphur

Solutions of two different sodium salts form when Na₂X(aq) reacts with ..........

1. A MgCO₃
2. B AgNO₃
3. C I₂
4. D S

The following figure shows a chemical experiment:
What is solution (1) and the anion of solution (2)?

1. A (1) : HCl(aq) , (2) : SO₄²⁻(aq)
2. B (1) : HCl(aq) , (2) : S₂O₃²⁻(aq)
3. C (1) : I₂(aq) , (2) : S₄O₆²⁻(aq)
4. D (1) : I₂(aq) , (2) : S₂O₃²⁻(aq)

The substance whose two parts are both oxidised by KMnO₄ solution in an acidic medium is ............

1. A Fe(NO₃)₂
2. B MgSO₃
3. C Ti(NO₂)₃
4. D K₂CO₃

The anion that changes the colour of acidified K₂Cr₂O₇ solution is ............

1. A NO₃⁻
2. B NO₂⁻
3. C HCO₃⁻
4. D CO₃²⁻

What happens when potassium permanganate solution acidified with conc. sulphuric acid is added to sodium nitrite?

1. A Only sodium nitrite is oxidised.
2. B Only potassium permanganate is reduced.
3. C The sodium ion is oxidised and the potassium ion is reduced.
4. D The nitrite ion is oxidised and the manganese ion is reduced.

When carbon monoxide gas is used to reduce the solid compound formed by strongly heating
iron(II) sulphate ............

1. A a gas forms that turns clear limewater milky.
2. B a group of gases forms, all of which turn clear limewater milky.
3. C a group of gases forms, one of which blackens a paper moistened with lead(II) acetate solution.
4. D a group of gases forms, one of which turns acidified potassium permanganate solution green.

From the following chart:
Which of the following is correct?

1. A (X) : Na₂SO₃ , (Y) : SO₂ , (Z) : black.
2. B (X) : NaNO₂ , (Y) : NO , (Z) : white.
3. C (X) : Na₂S , (Y) : H₂S , (Z) : black.
4. D (X) : Na₂CO₃ , (Y) : CO₂ , (Z) : white.

When each of the substances (W) and (X) reacts with dilute hydrochloric acid, the gases (Y) and (Z) are given off respectively.
• Gas (Y): turns acidified potassium dichromate solution green.
• Gas (Z): is oxidised in air forming a reddish-brown gas.
What are the two anions present in substances (W) and (X)?

1. A (W) : sulphite , (X) : sulphide.
2. B (W) : bicarbonate , (X) : nitrite.
3. C (W) : sulphite , (X) : nitrite.
4. D (W) : sulphide , (X) : bicarbonate.

When dilute hydrochloric acid is added to the salts (X) and (Y) - each alone - a gas is given off
that does not affect potassium permanganate solution acidified with sulphuric acid.
Salts (X) and (Y) are ..........

1. A (X) : KNO₂ , (Y) : K₂CO₃
2. B (X) : K₂SO₃ , (Y) : K₂S₂O₃
3. C (X) : KNO₃ , (Y) : K₂SO₃
4. D (X) : KHCO₃ , (Y) : K₂CO₃

The number of moles of KMnO₄ needed to react completely with 0.05 mol of sodium nitrite in an acidic medium is ............

1. A 0.125 mol
2. B 0.02 mol
3. C 0.2 mol
4. D 2 mol

Dilute sulphuric acid can be used to detect the anions ..........

1. A S₂O₃²⁻ , NO₃⁻ , SO₃²⁻ , CO₃²⁻
2. B NO₂⁻ , S²⁻ , S₂O₃²⁻ , SO₃²⁻
3. C NO₃⁻ , I⁻ , S₂O₃²⁻ , SO₃²⁻
4. D NO₂⁻ , NO₃⁻ , SO₃²⁻ , CO₃²⁻

KCl(s) and KBr(s) can be distinguished using ............

1. A H₂SO₃(aq)
2. B HNO₃(l)
3. C H₂SO₄(l)
4. D HNO₂(aq)

Sodium chloride solution and sodium nitrate solution can be distinguished using ............

1. A dilute hydrochloric acid.
2. B potassium carbonate solution.
3. C silver nitrate solution.
4. D dilute sulphuric acid.

Which of the following salt solutions gives a white precipitate when added to AgNO₃?

1. A Cu(NO₃)₂
2. B Na₂S
3. C BaCl₂
4. D KI

The ions present in the solution formed by adding excess silver nitrate to sodium chloride solution are ............

1. A Cl⁻ , Na⁺
2. B Na⁺ , NO₃⁻ , Cl⁻
3. C Ag⁺ , Na⁺ , Cl⁻
4. D Na⁺ , NO₃⁻ , Ag⁺

Acid (X) is used as the basic reagent for the chloride and bromide anions; when it reacts with excess iron filings
and heating, the ions .......... form.

1. A SO₄²⁻ , Fe²⁺
2. B Cl⁻ , Fe²⁺
3. C SO₄²⁻ , Fe³⁺ , Fe²⁺
4. D Cl⁻ , Fe³⁺ , Fe²⁺

In the chemical reaction shown by the following equation:
2AgNO₃ + BaCl₂ ⟶ 2AgCl + Ba(NO₃)₂
Which of the following shows the solubility in water of the reacting salts and the products?

1. A Soluble in water: silver nitrate ; insoluble in water: barium chloride , barium nitrate , silver chloride
2. B Soluble in water: silver nitrate , barium chloride ; insoluble in water: barium nitrate , silver chloride
3. C Soluble in water: silver nitrate , barium chloride , barium nitrate ; insoluble in water: silver chloride
4. D Soluble in water: silver nitrate , barium chloride , silver chloride ; insoluble in water: barium nitrate

The reactions shown in the following chart take place under suitable conditions:
Which of the following is correct?

1. A (1) : Na₂S , (2) : NaI , (3) : Na₂SO₃
2. B (1) : Pb(NO₃)₂ , (2) : Na₂SO₃ , (3) : Na₂CO₃
3. C (1) : Na₂S , (2) : NaCl , (3) : Na₂SO₃
4. D (1) : Pb(NO₃)₂ , (2) : Na₂SO₃ , (3) : Na₂CO₃

Which of the following equations represents the final reaction between conc. sulphuric acid and sodium bromide salt?

1. A 2NaBr(s) + H₂SO₄(aq) ⟶(Δ) Na₂SO₄(aq) + 2HBr(g)
2. B 2NaBr(s) + H₂SO₄(l) ⟶(Δ) Na₂SO₄(aq) + 2HBr(g)
3. C 2NaBr(s) + 2H₂SO₄(l) ⟶(Δ) Na₂SO₄(aq) + 2H₂O(l) + SO₂(g) + Br₂(v)
4. D 2NaBr(s) + 2H₂SO₄(aq) ⟶(Δ) Na₂SO₄(aq) + 2H₂O(l) + SO₂(g) + Br₂(v)

The reaction of a solid sodium salt with the hot concentrated acid prepared by the contact process gives all of the following,
except ..........

1. A a gas that is partly oxidised.
2. B a salt solution whose anion is detected by HCl(aq)
3. C a vapour that turns starch solution yellow.
4. D a gas that is affected by acidified K₂Cr₂O₇ solution.

From the following chart:
Which of the following describes substance (A)?

1. A A yellowish-white precipitate.
2. B A white precipitate.
3. C A yellow precipitate.
4. D A black precipitate.

A colourless solution forms when sodium metal is added to acid (X), and when silver nitrate solution is added
to this solution a precipitate forms that darkens when exposed to light.
What is the chemical formula of acid (X), and what is the effect of concentrated ammonia solution on the precipitate?

1. A H₂S(aq) / does not dissolve.
2. B HBr(aq) / dissolves.
3. C HNO₂(aq) / does not dissolve.
4. D HCl(aq) / dissolves.

What role does hot conc. sulphuric acid play when it is added in excess to sodium bromide salt?

1. A Oxidising agent.
2. B Reducing agent.
3. C Dehydrating agent.
4. D Catalyst.

A sufficient amount of silver nitrate solution was added to a mixture of sodium chloride and potassium iodide solutions.
What is the effect of adding excess concentrated ammonia solution to the products of the two previous reactions?

1. A A yellowish-white precipitate forms.
2. B A white precipitate forms.
3. C A yellow precipitate forms.
4. D No precipitate forms.

A white salt whose solution reacts with concentrated silver nitrate solution forming a precipitate that does not dissolve in ammonia solution,
and when the same salt reacts with hot conc. sulphuric acid, a mixture of .......... is given off.

1. A NO , NO₂
2. B SO₂ , I₂
3. C SO₂ , Br₂
4. D H₂S , Cl₂

One of the gases dissolves in water forming compound (X), which reacts with gas (Y) under suitable conditions forming a coloured
vapour, whose solution is used to detect the S₂O₃²⁻ anion.
Which of the following is correct?

1. A (X) : HCl , (Y) : NH₃
2. B (X) : H₂SO₄ , (Y) : HCl
3. C (X) : H₂SO₄ , (Y) : HI
4. D (X) : HCl , (Y) : HBr

The following table shows the results of two experiments carried out on compound (X):
• Experiment: adding silver nitrate solution to a solution of compound (X), then adding ammonia solution to the product ; Observation: a precipitate forms that does not dissolve in ammonia solution.
• Experiment: heating solid compound (X) with conc. sulphuric acid ; Observation: violet fumes are given off.
Compound (X) is ............

1. A iron(II) chloride
2. B lithium bromide.
3. C potassium sulphate.
4. D sodium iodide.

When pale yellow FeCl₃ solution is added to colourless KI solution, a brown solution forms as a result of
............

1. A oxidation of Fe³⁺ ions
2. B oxidation of I⁻ ions
3. C reduction of I⁻ ions
4. D reduction of Cl⁻ ions

What colour change takes place when potassium iodide solution is oxidised by acidified KMnO₄ solution,
and when acidified potassium dichromate solution is reduced by SO₂ gas?

1. A Colour change in the oxidation: from violet to brown ; colour change in the reduction: from green to orange
2. B Colour change in the oxidation: from violet to brown ; colour change in the reduction: from orange to green
3. C Colour change in the oxidation: from colourless to violet ; colour change in the reduction: from green to orange
4. D Colour change in the oxidation: from colourless to violet ; colour change in the reduction: from orange to green

From the opposite reaction:
2KI(aq) + Fe₂(SO₄)₃(aq) ⟶ K₂SO₄(aq) + I₂(aq) + 2FeSO₄(aq)
All of the following are correct, except ............

1. A The magnetic moment of the iron cation decreases.
2. B Reduction of the iodide anion takes place.
3. C One of the products is affected by acidified KMnO₄(aq).
4. D One of the products is used to detect S₂O₃²⁻(aq)

From the reaction:
2KI(aq) + Fe₂(SO₄)₃(aq) ⟶ K₂SO₄(aq) + I₂(aq) + 2FeSO₄(aq)
Which of the following is correct after the reaction ends?

1. A The number of unpaired electrons in the cation of the transition element increases.
2. B The number of unpaired electrons in the cation of the transition element decreases.
3. C The brown colour of iodine disappears.
4. D The solution turns violet.

From the following chart:
Which of the following is correct?

1. A (A) : CuSO₄ , (B) : CuI₂ , (C) : CuCO₃
2. B (A) : AgNO₃ , (B) : AgI , (C) : Ag₂CO₃
3. C (A) : AgNO₃ , (B) : KNO₃ , (C) : Ag₂CO₃
4. D (A) : Ca(NO₃)₂ , (B) : KNO₃ , (C) : CaCO₃

A solid mixture (X):
• reacts with dilute HCl acid forming a gas that turns clear limewater milky.
• its solution reacts with silver nitrate solution forming a yellow precipitate.
The anions present in mixture (X) are ..........

1. A I⁻ , CO₃²⁻
2. B CO₃²⁻ , Cl⁻
3. C SO₄²⁻ , Cl⁻
4. D SO₄²⁻ , I⁻

Which of the following silver salts dissolves neither in water nor in ammonia solution?

1. A AgHCO₃
2. B AgBr
3. C AgCl
4. D AgI

What are the similarities between the compounds AgCl, AgBr and AgI?

1. A Colour : wrong , solubility in NH₄OH : correct , sparingly soluble in H₂O : correct
2. B Colour : correct , solubility in NH₄OH : correct , sparingly soluble in H₂O : correct
3. C Colour : wrong , solubility in NH₄OH : correct , sparingly soluble in H₂O : wrong
4. D Colour : wrong , solubility in NH₄OH : wrong , sparingly soluble in H₂O : correct

When a small amount of colourless potassium iodide solution is added to colourless solution (X), the resulting
solution turns brown, and when the same amount of acidified potassium permanganate solution is added to solution (X),
the violet colour of the permanganate disappears. Which of the following describes solution (X)?

1. A It acts as an oxidising agent and as a reducing agent.
2. B It acts as an oxidising agent only.
3. C It acts neither as an oxidising agent nor as a reducing agent.
4. D It acts as a reducing agent only.

Fumes of colour (1) are given off when hot conc. sulphuric acid is added to the solid salt of anions (2).
All of the following may describe the colour of fumes (1) and anions (2), except ..........

1. A (1) : reddish orange , (2) : bromide.
2. B (1) : violet , (2) : iodide.
3. C (1) : reddish brown , (2) : nitrate.
4. D (1) : white , (2) : chloride.

A sodium salt reacts with hot H₂SO₄(l) forming acid (X), which reacts with metal (Y) under suitable conditions
and a coloured gas (Z) is given off.
Which of the following is correct?

1. A (X) : HNO₂ , (Y) : Fe , (Z) : NO₂
2. B (X) : HNO₃ , (Y) : Fe , (Z) : NO
3. C (X) : HNO₂ , (Y) : Cu , (Z) : NO
4. D (X) : HNO₃ , (Y) : Cu , (Z) : NO₂

When each of the following two experiments is carried out:
• Experiment (1): adding hot conc. nitric acid to copper turnings.
• Experiment (2): adding dilute hydrochloric acid to scandium carbonate powder.
then ............

1. A a colourless gas is given off in experiment (1).
2. B a coloured gas is given off in experiment (2).
3. C a coloured gas forms in experiment (1).
4. D a coloured gas forms in both experiments (1) and (2).

From the opposite chart:
The chemical formula of salt (X) is ..........

1. A NH₄NO₃
2. B NH₄Cl
3. C KNO₃
4. D Ba(NO₃)₂

Iron reacts with dilute sulphuric acid forming solution (X), which forms a brown compound when it combines with ............

1. A N₂O
2. B NO
3. C N₂O₃
4. D N₂O₅

The brown ring test for the nitrate anion depends on ..........

1. A reduction of the nitrogen of the nitrate ion.
2. B reduction of iron(II) sulphate
3. C oxidation of the nitrogen of the nitrate ion.
4. D oxidation of sulphuric acid.

Which of the following processes takes place under suitable conditions and is accompanied by the release of only one gaseous substance?

1. A Thermal decomposition of HNO₃ acid
2. B The reaction of hydrogen iodide with H₂SO₄
3. C Strongly heating the compound FeCO₃
4. D Strongly heating the compound FeSO₄

When hot conc. sulphuric acid is added to:
• salt (X): a gas that can be oxidised is given off.
• salt (Y): a gas that is hard to oxidise is given off.
Which of the following is correct?

1. A (X) : NaCl , (Y) : NaBr
2. B (X) : NaNO₃ , (Y) : NaI
3. C (X) : NaNO₂ , (Y) : Na₂SO₃
4. D (X) : NaI , (Y) : NaNO₃

From the opposite chart:
The chemical formula of substance (X) is ............

1. A NH₄NO₃
2. B Pb(NO₃)₂
3. C Ag₂SO₃
4. D NaCl

When conc. sulphuric acid is added to salt (X) with heating, gas (Y) is given off and precipitate (Z) forms.
Which of the following is correct?

1. A (X) : Na₂CO₃ , (Y) : CO₂ , (Z) : Na₂SO₄
2. B (X) : CaCl₂ , (Y) : Cl₂ , (Z) : CaSO₄
3. C (X) : Mg(NO₃)₂ , (Y) : NO₂ , (Z) : MgSO₄
4. D (X) : Pb(NO₃)₂ , (Y) : NO₂ , (Z) : PbSO₄

Among the compounds that dissolve in water are ..........

1. A barium chloride , calcium carbonate , magnesium hydroxide.
2. B barium sulphate , calcium hydroxide , ammonium carbonate.
3. C barium chloride , ammonium hydroxide , magnesium sulphate.
4. D barium sulphate , calcium sulphate , magnesium hydroxide.

A white precipitate forms when either conc. sulphuric acid or silver nitrate solution is added to a solution of ..........

1. A magnesium chloride.
2. B magnesium sulphate.
3. C barium chloride.
4. D barium nitrate.

The two salts formed by the combination of the Ba²⁺ cation with anion (1) and with anion (2) share property (3).
Which of the following is correct?

1. A (1) : CO₃²⁻ , (2) : PO₄³⁻ , (3) : solubility in HCl
2. B (1) : HCO₃⁻ , (2) : SO₄²⁻ , (3) : solubility in H₂O
3. C (1) : SO₄²⁻ , (2) : CO₃²⁻ , (3) : solubility in HCl
4. D (1) : CO₃²⁻ , (2) : PO₄³⁻ , (3) : solubility in H₂O

The following anions can form salts that do not dissolve in water, except ..........

1. A SO₄²⁻
2. B Cl⁻
3. C NO₃⁻
4. D SO₃²⁻

A solution of a salt was divided into two parts: dilute nitric acid was added to the first and conc. sulphuric acid to the second,
and no reaction took place.
Which anion is probably present in the solution of this salt?

1. A Nitrate.
2. B Sulphide.
3. C Sulphite.
4. D Phosphate.

In each of the following pairs of anions one of them can be separated as a precipitate, except ..........

1. A NO₃⁻ , CO₃²⁻
2. B NO₃⁻ , NH₄⁺
3. C NH₄⁺ , PO₄³⁻
4. D SO₄²⁻ , SO₃²⁻

Silver and barium cations form a precipitate with both of the anions ..........

1. A phosphate and sulphate.
2. B nitrate and sulphite.
3. C bicarbonate and sulphate.
4. D chloride and sulphite.

An anhydrous white salt (Z) was strongly heated, forming a solid (X) and a gaseous mixture; then the solid (X) was dissolved in
dilute hydrochloric acid, and when drops of dilute sulphuric acid were added to the resulting solution a white precipitate formed.
Salt (Z) is ..........

1. A copper carbonate.
2. B magnesium nitrate.
3. C magnesium carbonate.
4. D barium nitrate.

The white salt that dissolves in concentrated NH₄OH solution and does not dissolve in H₂O is ..........

1. A CuSO₄
2. B AgI
3. C AgCl
4. D Ag₃PO₄

Sodium chloride solution and lead(II) nitrate solution can be distinguished by each of the following, except ..........

1. A dilute sulphuric acid.
2. B silver nitrate solution.
3. C potassium bicarbonate solution.
4. D hydrogen sulphide gas.

The cation of metal (M) combines with the sulphate anion forming a white precipitate (Y).
Which of the following gives metal (M) and how soluble precipitate (Y) is in different acids?

1. A (M) : Ba , (Y) : dissolves in dilute HCl acid.
2. B (M) : Mg , (Y) : does not dissolve in conc. H₂SO₄ acid.
3. C (M) : Mg , (Y) : dissolves in conc. H₂SO₄ acid.
4. D (M) : Ba , (Y) : does not dissolve in dilute HCl acid.

Silver nitrate solution forms each of the following precipitates, except ..........

1. A a yellow precipitate with the phosphate ion.
2. B a white precipitate with the iodide ion.
3. C a white precipitate with the sulphite ion.
4. D a yellowish-white precipitate with the bromide ion.

Pollution of drinking water by lead compounds is one of the main causes of disease, so water treatment plants
remove lead ions.
Which substance can be used for this purpose?

1. A Sodium bicarbonate.
2. B Magnesium sulphate.
3. C Acetic acid.
4. D Nitric acid.

A solution is made of a mixture of Cl⁻ and SO₄²⁻ ions.
Which cation, when added to the solution, precipitates one of the two anions but not the other?

1. A Mg²⁺
2. B Ba²⁺
3. C Fe³⁺
4. D Fe²⁺

When a mixture of solutions of barium nitrate, iron(II) sulphate and magnesium chloride is shaken,
the number of precipitates formed is ..............

1. A 1
2. B 2
3. C 3
4. D 4

Which of the following gives the anions that form coloured fumes when hot conc. sulphuric acid is added to their solid salt?

1. A Br⁻ : correct , NO₃⁻ : wrong , PO₄³⁻ : correct
2. B Br⁻ : wrong , NO₃⁻ : correct , PO₄³⁻ : wrong
3. C Br⁻ : correct , NO₃⁻ : correct , PO₄³⁻ : wrong
4. D Br⁻ : wrong , NO₃⁻ : wrong , PO₄³⁻ : correct

Dilute hydrochloric acid was added to a solution containing Ag⁺, Ba²⁺, Mn²⁺ and Cu²⁺ ions,
and precipitate (X) formed; after separating precipitate (X), sulphuric acid was added to the remaining solution and precipitate (Y) formed.
Which of the following is correct?

1. A (X) : AgCl , (Y) : BaSO₄
2. B (X) : BaCl₂ , (Y) : Ag₂SO₄
3. C (X) : AgCl , (Y) : MnSO₄
4. D (X) : MnCl₂ , (Y) : CuSO₄

Mixture (X) contains equal amounts of the nitrate and sulphate of a group 2A metal; when water was added to
mixture (X) one of the two compounds dissolved, while the other precipitated, and after separating the mixture by filtration the resulting solution was found
to react with sulphuric acid forming a precipitate. Which of the following describes mixture (X)?

1. A Ba(NO₃)₂ + BaSO₄
2. B Ba(NO₃)₂ + MgSO₄
3. C Mg(NO₃)₂ + BaSO₄
4. D Mg(NO₃)₂ + MgSO₄

The phosphate anion in sodium phosphate solution can be detected using calcium nitrate solution.
What is the sum of the coefficients in the balanced equation of the reaction, and the coefficient of the precipitate formed, respectively?

1. A 11 / 1
2. B 12 / 1
3. C 11 / 2
4. D 12 / 2

Cations (A) combine with carbonate anions forming a white precipitate that dissolves in dilute hydrochloric acid,
and the same cations combine with phosphate anions forming precipitate (B); cations (C) combine with chloride anions
forming a white precipitate that dissolves in ammonia solution, and the same cations combine with phosphate anions forming precipitate (D).
Which of the following is correct?

1. A Precipitate (B): a white precipitate that does not dissolve in HCl acid ; precipitate (D): a reddish-brown precipitate that dissolves in ammonia solution
2. B Precipitate (B): a white precipitate that dissolves in HCl acid ; precipitate (D): a yellow precipitate that dissolves in nitric acid
3. C Precipitate (B): a reddish-brown precipitate that dissolves in HCl acid ; precipitate (D): a reddish-brown precipitate that dissolves in ammonia solution
4. D Precipitate (B): a reddish-brown precipitate that does not dissolve in HCl acid ; precipitate (D): a white precipitate that dissolves in nitric acid

Which of the following graphs represents adding excess silver nitrate solution to a mixture of potassium phosphate
and potassium chloride solutions, then adding excess concentrated ammonia solution to the products?

1. A Graph (A)
2. B Graph (B)
3. C Graph (C)
4. D Graph (D)

What are the steps followed to separate a mixture of the salts barium phosphate and barium nitrate?

1. A Dissolving → evaporating → filtering.
2. B Dissolving → filtering → evaporating.
3. C Filtering → evaporating → dissolving.
4. D Filtering → dissolving → evaporating.

The opposite chart shows some reactions of compound (X).
Which of the following describes compound (X)?

1. A Mg(NO₃)₂
2. B CuSO₄
3. C H₂SO₄
4. D AgNO₃

From the opposite chart:
Mixture (X) contains the two anions ..........

1. A HCO₃⁻ , SO₄²⁻
2. B PO₄³⁻ , SO₄²⁻
3. C CO₃²⁻ , PO₄³⁻
4. D Cl⁻ , NO₃⁻

Solution (X) contains a mixture of two salts, and the following chart shows the results of some reactions of this solution:
All of the following describe the two salts of solution (X), except ..............

1. A CuSO₄ , KI
2. B ZnCl₂ , Sc₂(SO₄)₃
3. C TiCl₄ , K₃PO₄
4. D ZnSO₄ , NaCl

The following chart shows a series of chemical reactions:
Which of the following is correct?

1. A Substance (A) is iron(II) oxide and precipitate (D) is black.
2. B Acid (B) is HCl and precipitate (D) turns violet when exposed to light.
3. C Substance (A) is iron filings and solution (C) is iron(III) chloride
4. D Acid (B) is H₂SO₄ and solution (C) does not form a precipitate with BaCl₂ solution

When iron(II) sulphate is strongly heated, compound (X) forms, and when compound (X) is reduced by carbon monoxide gas,
gas (Y) forms:
(1) Write the balanced symbolic equation for the reduction of compound (X) to form gas (Y) at a temperature above 700°C
(2) Explain how gas (Y) is detected.

A sample of an iron ore with a yellowish-grey colour was divided into two equal parts (X) and (Y):
• Part (X): heated in the absence of air until its mass was constant, then dilute HCl acid was added to it.
• Part (Y): dilute HCl acid was added to it without heating.
(1) Write the equations of the two reactions that take place for part (X).
(2) Write the equation for detecting the gas formed for part (Y).

What do you observe when dilute sulphuric acid is added to each of:
(1) sodium carbonate salt.
(2) barium chloride salt.

What is the effect of passing the gas formed from:
(1) roasting siderite through calcium hydroxide solution.
(2) the oxidation of one of the impurities in siderite ore during roasting through acidified potassium dichromate solution.

Salt (X) reacts with dilute hydrochloric acid forming a gas that turns acidified potassium dichromate solution green:
(1) What is the anion of salt (X)?
(2) If all the salts formed by the cation of salt (X) dissolve in water, what are the possible cations of salt (X)?

The metals (X) and (Y) belong to the first transition series, and their compounds KXO₄ and K₂Y₂O₇ are used as oxidising agents.
(1) What is the highest oxidation state of:
(a) element (X).
(b) element (Y).
(2) What is the colour of the aqueous solution of:
(a) KXO₄
(b) K₂Y₂O₇

What gases are formed from the reaction of:
(1) dilute hydrochloric acid with a solid mixture of the salts sodium carbonate, nitrate, sulphide and sulphate.
(2) conc. sulphuric acid with a solid mixture of the salts sodium bicarbonate, phosphate and chloride.

(A) and (B) are two solutions of potassium salts; silver nitrate solution was added to each of them and a yellow precipitate formed in each,
and when dilute nitric acid was added to each of the two precipitates, the precipitate from solution (A) was found to dissolve in the acid,
while the precipitate from solution (B) did not dissolve in the acid.
Write the symbolic equation for the basic detection test of the anion of:
(1) salt (A).
(2) salt (B).

Adding dilute hydrochloric acid to:
• the two anions (1) and (2) forms the odourless gas (X).
• the two anions (3) and (4) forms gas (Y), which has a pungent smell.
Write the chemical formulas of the anions (1) to (4).

When barium chloride solution is added to two different solutions of sodium salts, a white precipitate forms in the first solution that dissolves
in dilute hydrochloric acid, and a white precipitate forms in the second solution that does not dissolve in dilute hydrochloric acid.
Write the chemical formula of each of the two precipitates formed.

Bottle (A) contains conc. hydrochloric acid, and bottle (B) contains concentrated ammonia solution.
What is the effect of bringing the mouths of the two bottles close to each other? Write the symbolic equation for the reaction.

The opposite figure shows a chemical reaction at its start.
Record two observations that can be seen with the naked eye showing that a chemical reaction has taken place.

Two salts (X) and (Y) both contain the same cation:
• (X): dissolves in water and dissolves in dilute acids.
• (Y): does not dissolve in water and dissolves in dilute acids.
When dilute hydrochloric acid is added to each of the two salts separately, gas (Z) is given off.
Which of the following describes gas (Z)?
(Sample exam 2026)

1. A It forms a white precipitate when passed through potassium hydroxide solution for a short time.
2. B It is given off when salt (X) is heated and salt (Y) forms.
3. C When passed through water containing salt (Y), the salt dissolves as sodium bicarbonate.
4. D When passed through clear limewater for a long time, it turns milky.

Dilute hydrochloric acid was added to each of three salts (X), (Y) and (Z) separately, and the results were as follows:
• For salt (X): a colourless gas that is easily oxidised was given off.
• For salt (Y): a white precipitate formed.
• For salt (Z): a gas was given off that blackens a paper moistened with lead(II) acetate.
Which of the following describes the salts (X), (Y) and (Z)?
(Sample exam 2026)

1. A (X) : NaNO₂ , (Y) : AgNO₃ , (Z) : Na₂S
2. B (X) : KNO₂ , (Y) : Pb(NO₃)₂ , (Z) : Na₂SO₃
3. C (X) : NH₄Cl , (Y) : Ag₂SO₄ , (Z) : Na₂SO₃
4. D (X) : NaNO₃ , (Y) : Ba(NO₃)₂ , (Z) : Na₂S

Conc. sulphuric acid was added to three solid salts (A), (B) and (C):
• For salt (A): a colourless gas that is hard to oxidise was given off.
• For salt (B): coloured fumes were given off, whose solution can be used to detect one of the anions of the first group.
• For salt (C): no gas was given off.
Which of the following describes the salts (A), (B) and (C)?
(Sample exam 2026)

1. A (A) : CaCl₂ , (B) : MgBr₂ , (C) : PbSO₄
2. B (A) : CaCl₂ , (B) : MgI₂ , (C) : Ag₃PO₄
3. C (A) : MgBr₂ , (B) : NaNO₃ , (C) : Ag₃PO₄
4. D (A) : CaI₂ , (B) : MgBr₂ , (C) : PbSO₄

When hot conc. sulphuric acid is added to salt (X), fumes are given off that turn a paper moistened with starch blue.
When barium chloride solution is added to a solution of salt (Y), a white precipitate forms that dissolves in dilute HCl acid.
Which of the following gives the result of adding silver nitrate solution to solutions of (X) and (Y)?
(Sample exam 2026)

1. A For the solution of salt (X): a yellow precipitate forms that dissolves in ammonia solution ; for the solution of salt (Y): a yellow precipitate forms that does not dissolve in ammonia solution
2. B For the solution of salt (X): a yellow precipitate forms that does not dissolve in ammonia solution ; for the solution of salt (Y): a yellow precipitate forms that dissolves in ammonia solution
3. C For the solution of salt (X): a yellowish-white precipitate forms ; for the solution of salt (Y): a yellow precipitate forms that does not dissolve in ammonia solution
4. D For the solution of salt (X): a white precipitate forms that dissolves in ammonia solution ; for the solution of salt (Y): a yellow precipitate forms that dissolves in ammonia solution

Two salts (Na₂X) and (NaY) were used in the experiments whose observations are shown in the following table:
• Experiment (solid salt + HCl(aq)): salt (Na₂X): a gas is given off ; salt (NaY): no gas is given off
• Experiment (salt solution + AgNO₃(aq)): salt (Na₂X): Ag₂X(s) forms ; salt (NaY): AgY(s) forms
Which of the following describes anion (X) or anion (Y) and their silver salts?
(Sample exam 2026)

1. A Anion (Y) is probably iodide and AgY(s) is a black precipitate.
2. B Anion (X) is probably sulphite and Ag₂X(s) is a white precipitate.
3. C Anion (X) is probably sulphide and Ag₂X(s) is a white precipitate.
4. D Anion (Y) is probably bromide and AgY(s) is a black precipitate.

When conc. sulphuric acid is added to salt (X), fumes (Y) are given off;
when a solution of these fumes is added to a solution of salt (Z), their colour disappears.
Which of the following describes (X), (Y) and (Z)?
(Sample exam 2026)

1. A (X) : NaI(s) , (Y) : I₂(v) , (Z) : Na₂S₂O₃(aq)
2. B (X) : NaBr(s) , (Y) : Br₂(v) , (Z) : Na₂S(aq)
3. C (X) : NaNO₃(s) , (Y) : NO₂(v) , (Z) : Na₂S(aq)
4. D (X) : NaI(s) , (Y) : I₂(v) , (Z) : Na₂SO₃(aq)

All of the following solutions can be used to distinguish between magnesium sulphate and magnesium chloride,
except ..........
(Sample exam 2026)

1. A barium chloride.
2. B hot conc. sulphuric acid.
3. C calcium bicarbonate.
4. D dilute hydrochloric acid.

When hot conc. sulphuric acid reacts with salt (X), a colourless gas is given off, while the same acid reacts with
salt (Y) and fumes are given off that turn a paper moistened with starch blue. Salts (X) and (Y) are ..........
(Sample exam 2026)

1. A (X) : sodium chloride , (Y) : sodium iodide
2. B (X) : sodium bromide , (Y) : sodium iodide
3. C (X) : sodium nitrate , (Y) : sodium sulphate
4. D (X) : sodium chloride , (Y) : sodium bromide

When a confirmatory reagent (X) is added to a solution of salt (Y), the colour of reagent (X) disappeared and salt (Y) was oxidised.
Which of the following describes reagent (X) and salt (Y)?
(Sample exam 2026)

1. A Reagent (X): acidified potassium permanganate , salt (Y): sodium nitrite
2. B Reagent (X): magnesium sulphate , salt (Y): sodium nitrate
3. C Reagent (X): lead(II) acetate , salt (Y): sodium sulphide
4. D Reagent (X): brown iodine solution , salt (Y): sodium sulphate

Hydrochloric acid solution was added to three solid salts (X), (Y) and (Z) separately, and the results were as follows:
• (X): a gas is given off that does not change the colour of acidified potassium permanganate solution.
• (Y): a suspension forms in the solution and a gas that affects acidified potassium permanganate solution.
• (Z): the colour of the solution does not change and no gas is given off.
Which of the following is correct for the salts (X), (Y) and (Z)?
(Sample exam 2026)

1. A Salt (X): silver bicarbonate , salt (Y): sodium thiosulphate , salt (Z): sodium nitrate
2. B Salt (X): sodium sulphite , salt (Y): sodium nitrate , salt (Z): sodium nitrite
3. C Salt (X): sodium carbonate , salt (Y): sodium thiosulphate , salt (Z): sodium sulphide
4. D Salt (X): sodium nitrate , salt (Y): sodium nitrite , salt (Z): sodium chloride

The following experiments were carried out on four salt solutions (X), (Y), (Z) and (W):
• Solution (X): a precipitate formed when calcium hydroxide solution was added.
• Solution (Y): no precipitate formed when calcium hydroxide solution was added.
• Solution (Z): decolourised iodine solution.
• Solution (W): a black precipitate formed when lead(II) nitrate was added.
Which of the following is correct for the salts (X), (Y), (Z) and (W)?
(Sample exam 2026)

1. A Salt (X): potassium bicarbonate , salt (Y): ammonium carbonate , salt (Z): sodium sulphide , salt (W): sodium thiosulphate
2. B Salt (X): ammonium carbonate , salt (Y): potassium bicarbonate , salt (Z): sodium thiosulphate , salt (W): sodium sulphide
3. C Salt (X): sodium thiosulphate , salt (Y): sodium sulphide , salt (Z): ammonium bicarbonate , salt (W): sodium sulphide
4. D Salt (X): sodium sulphide , salt (Y): sodium thiosulphate , salt (Z): ammonium carbonate , salt (W): sodium bicarbonate

Which of the following is not used to distinguish between nitric oxide gas and hydrogen chloride gas?
(Sample exam 2026)

1. A Sodium chloride solution.
2. B Exposing each of them separately to air.
3. C A rod moistened with ammonia.
4. D Acidified potassium permanganate.

The experiments shown in the following table were carried out to identify three acids:
• Experiment (1): hydrogen bromide gas was passed through hot concentrated acid (1) ; observation: orange fumes were given off
• Experiment (2): exposing a rod moistened with ammonia to the fumes of acid (2) ; observation: white clouds formed
• Experiment (3): adding barium nitrate solution to a solution of dilute acid (3) ; observation: a white precipitate formed
Which of the following describes the acids (1), (2) and (3)?
(Sample exam 2026)

1. A Acid (1): sulphuric acid , acid (2): hydrochloric acid , acid (3): phosphoric acid
2. B Acid (1): hydrochloric acid , acid (2): phosphoric acid , acid (3): nitric acid
3. C Acid (1): nitric acid , acid (2): sulphuric acid , acid (3): phosphoric acid
4. D Acid (1): sulphuric acid , acid (2): hydrochloric acid , acid (3): nitric acid

Each of the following is a reaction that produces substances sparingly soluble in water, except ..........
(Sample exam 2026)

1. A Magnesium sulphate solution with potassium bicarbonate solution.
2. B Dilute hydrochloric acid with potassium thiosulphate salt.
3. C Silver nitrate solution with potassium sulphite solution.
4. D Carbon dioxide with calcium hydroxide solution for a short time.

When dilute hydrochloric acid is added to a salt whose anion is (X²⁻), gas (Y) is given off, which is oxidised by common oxidising agents.
Which of the following applies to anion (X²⁻) and gas (Y)?
(Sample exam 2026)

1. A Anion (X²⁻): nitrite , gas (Y): colourless, turns reddish brown in air
2. B Anion (X²⁻): sulphite , gas (Y): has a pungent smell and turns acidified potassium dichromate solution green
3. C Anion (X²⁻): sulphide , gas (Y): odourless and gives a black precipitate with lead(II) acetate solution
4. D Anion (X²⁻): carbonate , gas (Y): colourless and odourless and turns clear limewater milky

Which of the following is not preferred for distinguishing between the nitrate and nitrite anions in their salts?
(Sample exam 2026)

1. A Dilute hydrochloric acid.
2. B Hot conc. sulphuric acid.
3. C Potassium permanganate solution acidified with sulphuric acid.
4. D Iron(II) sulphate with drops of conc. sulphuric acid.

Acid (X) was added to three salts (A), (B) and (C):
• For (A): a colourless gas was given off that is partly oxidised to violet fumes.
• For (B): a colourless gas was given off that is partly oxidised to orange fumes.
• For (C): a reddish-brown gas was given off.
Which of the following describes acid (X) and the salts (A), (B) and (C)?
(Sample exam 2026)

1. A Acid (X): dilute hydrochloric , salt (A): CaI₂ , salt (B): MgBr₂ , salt (C): Pb(NO₃)₂
2. B Acid (X): concentrated nitric , salt (A): NaNO₃ , salt (B): NaI , salt (C): NaBr
3. C Acid (X): concentrated sulphuric , salt (A): NaBr , salt (B): NaNO₃ , salt (C): NaI
4. D Acid (X): concentrated sulphuric , salt (A): CaI₂ , salt (B): MgBr₂ , salt (C): Pb(NO₃)₂

From the following chart:
Which of the following is correct?
(Sample exam 2026)

1. A Solution (X): Na₂SO₄ , precipitate (A): Ba₃(PO₄)₂
2. B Solution (X): Na₂CO₃ , precipitate (A): BaSO₄
3. C Solution (X): Na₂SO₄ , precipitate (A): BaCO₃
4. D Solution (X): Na₂CO₃ , precipitate (A): Ba₃(PO₄)₂

Which of the following describes the effect of the gas formed from (the reaction of dilute hydrochloric acid with sodium sulphite)?
(Sample exam 2026)

1. A It turns a paper moistened with acidified potassium dichromate solution green.
2. B It does not decolourise potassium permanganate solution acidified with conc. sulphuric acid.
3. C It blackens a paper moistened with lead(II) acetate solution.
4. D It turns a paper moistened with starch yellow.

Which of the following reactions produces a precipitate?
(Sample exam 2026)

1. A Hydrogen sulphide gas with lead(II) acetate solution.
2. B Sodium thiosulphate solution with brown iodine solution.
3. C Sulphur dioxide gas with potassium dichromate solution acidified with conc. sulphuric acid.
4. D Sodium nitrite solution with potassium permanganate solution acidified with conc. sulphuric acid.

When hot conc. sulphuric acid reacts with salt (X), a gas is given off that the acid hardly oxidises, and when the same acid reacts with salt (Y), a gas is given off that is partly oxidised. Salts (X) and (Y) are ..........
(Sample exam 2026)

1. A Salt (X): sodium chloride , salt (Y): sodium iodide
2. B Salt (X): sodium bromide , salt (Y): sodium iodide
3. C Salt (X): sodium nitrate , salt (Y): sodium carbonate
4. D Salt (X): sodium chloride , salt (Y): sodium sulphate

When barium chloride solution is added to a solution of salt (X), a white precipitate forms that dissolves in dilute acids, and when lead(II) acetate solution is added to a solution of salt (Y), a white precipitate forms.
Which of the following describes the anions of salts (X) and (Y)?
(Sample exam 2026)

1. A Anion of salt (X): phosphate , anion of salt (Y): sulphate
2. B Anion of salt (X): phosphate , anion of salt (Y): sulphide
3. C Anion of salt (X): sulphate , anion of salt (Y): phosphate
4. D Anion of salt (X): chloride , anion of salt (Y): sulphate

Which pair of the following salts can be distinguished using hydrochloric acid?
(Sample exam 2026)

1. A Na₂SO₃ , Na₃PO₄
2. B NaCl , NaBr
3. C NaI , NaNO₃
4. D NaHCO₃ , Na₂CO₃

Which of the following cannot be used to distinguish between a calcium carbonate precipitate and a silver phosphate precipitate?
(Sample exam 2026)

1. A The different colour of the two precipitates.
2. B Adding water in which carbon dioxide is dissolved.
3. C Adding ammonium hydroxide (NH₄OH) solution.
4. D Adding acidified KMnO₄ solution to each of them.

A mixture of hydrogen sulphide and sulphur dioxide gases is given off from a factory.
Which of the following solutions can be used to get rid of these gases, each separately?
(Sample exam 2026)

1. A Sodium chloride solution, then lead(II) acetate.
2. B Hydrochloric acid, then acidified potassium permanganate.
3. C Lead(II) nitrate solution, then copper sulphate solution.
4. D Lead(II) acetate, then acidified potassium dichromate.

A solution of salt (X) reacted with each of:
• silver nitrate solution, and a white precipitate formed.
• ammonium carbonate solution, and a white precipitate formed.
Which of the following describes salt (X)?
(Sample exam 2026)

1. A Calcium chloride.
2. B Calcium phosphate.
3. C Sodium chloride.
4. D Lead(II) nitrate.

Dilute hydrochloric acid was added to three solid salts (A), (B) and (C), each separately:
• For (A): a colourless gas was given off.
• For (B): a gas was given off that is oxidised in air.
• For (C): no reaction took place.
Which describes the anions of these salts?
(1st session 2025)

1. A Anion of salt (A): NO₂⁻ , anion of salt (B): S₂O₃²⁻ , anion of salt (C): SO₃²⁻
2. B Anion of salt (A): CO₃²⁻ , anion of salt (B): NO₂⁻ , anion of salt (C): PO₄³⁻
3. C Anion of salt (A): SO₄²⁻ , anion of salt (B): NO₂⁻ , anion of salt (C): CO₃²⁻
4. D Anion of salt (A): CO₃²⁻ , anion of salt (B): SO₃²⁻ , anion of salt (C): PO₄³⁻

Dilute nitric acid was added to solid salt (X) and a gas was given off that is oxidised in air, and when sodium sulphate solution was added to a solution of salt (X), a white precipitate formed.
Which of the following choices gives the chemical formula of salt (X)?
(1st session 2025)

1. A Ca(NO₂)₂
2. B Cu(NO₂)₂
3. C Pb(HCO₃)₂
4. D Fe(SO₃)₃

Which of the following does not distinguish between the main reagent of the nitrite ion and the main reagent of the nitrate ion?
(Sample exam 2025)

1. A Sodium chloride.
2. B Sodium iodide.
3. C Sodium thiosulphate.
4. D Barium chloride.

(X) and (Y) are two magnesium salts of the same acid.
• Salt (X): does not dissolve in water and dissolves in dilute acids.
• Salt (Y): dissolves in water and in dilute acids.
Each of them is placed in a separate test tube containing some water, then carbon dioxide gas is passed through each of them.
Which of the following choices is correct?
(2nd session 2024)

1. A Salt (Y) changes into salt (X).
2. B Salt (X) changes into salt (Y).
3. C The two salts change into the acid they are formed from.
4. D The two salts remain unchanged.

Which of the following salts gives a gas and a substance sparingly soluble in water when hot conc. sulphuric acid is added to it?
(2nd session 2024)

1. A BaCl₂
2. B NaCl
3. C (CH₃COO)₂Mg
4. D Cu(NO₃)₂

The anion of the salt that is oxidised by oxidising agents and does not form a precipitate with magnesium chloride solution is ..........
(2nd session 2024)

1. A nitrate.
2. B carbonate.
3. C bicarbonate.
4. D nitrite.

When silver nitrate solution is added to solutions of two salts (A) and (B) - each separately - a yellow precipitate forms in each of them.
Which of the following is used to distinguish between the two precipitates formed?
(2nd session 2024)

1. A Barium chloride solution.
2. B Sodium hydroxide solution.
3. C Ammonium hydroxide solution.
4. D Magnesium sulphate solution.

Ammonium carbonate solution may be used to identify all of the following cations, except ..........
(2nd session 2022)

1. A Ca²⁺
2. B Mg²⁺
3. C Na⁺
4. D Ag²⁺

Two chemical compounds (A) and (B): heating compound (A) gives a gas used in reducing iron oxides, and heating compound (B) gives a gas that changes the colour of a paper moistened with potassium dichromate solution acidified with conc. sulphuric acid from orange to green.
Which of the following correctly describes compounds (A) and (B)?
(Trial exam / May 2021)

1. A Compound (A): iron(II) sulphate , compound (B): iron(III) hydroxide
2. B Compound (A): iron(II) carbonate , compound (B): iron(III) chloride
3. C Compound (A): iron(II) oxalate , compound (B): iron(II) sulphate
4. D Compound (A): iron(III) sulphate , compound (B): iron(III) oxide

In the chemical equation:
Salt + 2HCl(aq) → 2NaCl(aq) + H₂O(l) + X(g)
Which of the following statements describes the gas formed (X)?
(2nd session 2022)

1. A It turns a paper moistened with acidified potassium dichromate solution green.
2. B It blackens a paper moistened with lead(II) acetate solution.
3. C It turns a paper moistened with starch solution yellow.
4. D It turns a paper moistened with starch solution blue.

When solution (X) is added to a solution containing anion (Y), a black precipitate forms, and when solution (X) is added to a solution containing anion (Z), a white precipitate forms that turns black on heating.
Solution (X) and the anions (Y) and (Z) are ..........
(1st session 2024)

1. A Solution (X): I₂ , anion (Y): I⁻ , anion (Z): SO₃²⁻
2. B Solution (X): AgNO₃ , anion (Y): SO₃²⁻ , anion (Z): S²⁻
3. C Solution (X): AgNO₃ , anion (Y): S²⁻ , anion (Z): SO₃²⁻
4. D Solution (X): KMnO₄ , anion (Y): NO₃⁻ , anion (Z): SO₄²⁻

Dilute HCl was added to a solid salt with the chemical formula (A₂X), and a gas was given off that forms a black precipitate with a paper moistened with B(Y)₂ solution.
Anion (Y) is ..........
(Trial exam / June 2021)

1. A CH₃COO⁻
2. B S²⁻
3. C SO₃²⁻
4. D HCO₃⁻

In the following chart:
Salt (X) is ..........
(2nd session 2023)

1. A Na₂SO₄
2. B Na₂SO₃
3. C Na₂S
4. D Na₂S₂O₃

Given that KMnO₄ is a strong oxidising agent,
the colour of acidified KMnO₄ disappears when it is added to the two solutions ..........
(Trial exam / June 2021)

1. A FeSO₄ , NaNO₂
2. B FeSO₄ , NaNO₃
3. C Fe₂(SO₄)₃ , KNO₂
4. D Fe₂(SO₄)₃ , NaNO₃

When silver nitrate solution is added to solutions of salts (A) and (B), a precipitate formed with the solution of salt (A) and no precipitate formed with the solution of salt (B).
The anions of the two salts, respectively, are ..........
(1st session 2021)

1. A (A) : sulphide , (B) : nitrite.
2. B (A) : nitrite , (B) : sulphide.
3. C (A) : bicarbonate , (B) : nitrite.
4. D (A) : nitrite , (B) : bicarbonate.

(X) and (Y) are two acids:
acid (X) can be used to detect the anion of acid (Y) in its salts.
The anions of acids (X) and (Y) are ..........
(1st session 2024)

1. A Anion of acid (X): chloride , anion of acid (Y): nitrite.
2. B Anion of acid (X): chloride , anion of acid (Y): sulphate.
3. C Anion of acid (X): nitrite , anion of acid (Y): nitrate.
4. D Anion of acid (X): nitrate , anion of acid (Y): sulphate.

The reagent that can be used to distinguish between HBr gas and HCl gas is ..........
(1st session 2024)

1. A hot conc. sulphuric acid.
2. B dilute hydrochloric acid.
3. C a paper moistened with starch.
4. D a moistened litmus paper.

Which of the following salts gives only one gas when hot conc. sulphuric acid is added to it in its solid state?
(1st session 2024)

1. A NaNO₃
2. B NaCl
3. C NaBr
4. D NaI

When silver nitrate solution is added to solutions of the two salts (A) and (B), a precipitate (X) forms with the solution of salt (A) that dissolves quickly in conc. ammonia solution, and a precipitate (Y) forms with the solution of salt (B) that dissolves slowly in conc. ammonia solution.
Precipitates (X) and (Y), respectively, are ..........
(Trial exam / June 2021)

1. A Precipitate (X): AgCl , precipitate (Y): AgBr
2. B Precipitate (X): AgCl , precipitate (Y): AgI
3. C Precipitate (X): AgBr , precipitate (Y): AgI
4. D Precipitate (X): AgI , precipitate (Y): BaSO₄

When a strong conc. mineral acid is added to the solid salts (X) and (Y) - each separately - a gas is given off with salt (X) whose colour differs from that of the gas given off with salt (Y).
Which of the following does not represent these observations?
(2nd session 2021)

1. A (X) : potassium bromide , (Y) : potassium iodide.
2. B (X) : potassium bromide , (Y) : potassium nitrate.
3. C (X) : potassium chloride , (Y) : potassium carbonate.
4. D (X) : potassium iodide , (Y) : potassium nitrate.

When conc. sulphuric acid is added to two salts, gas (X), which turns a paper moistened with starch solution yellow, is given off with one of them, and gas (Y), which turns a paper moistened with starch solution blue, is given off with the other.
The two gases are ..........
(1st session 2021)

1. A Gas (X): NO₂(g) , gas (Y): I₂(v)
2. B Gas (X): HBr(g) , gas (Y): HI(g)
3. C Gas (X): HCl(g) , gas (Y): Br₂(v)
4. D Gas (X): Br₂(g) , gas (Y): I₂(v)

When hot conc. H₂SO₄ is added to each of the solid salts (A), (B), (C) and (D) separately, the observations shown in the following table occur:
• Salt (A): a colourless gas that forms white clouds with a rod moistened with NH₄OH
• Salt (B): reddish-orange fumes that turn a paper moistened with starch yellow
• Salt (C): violet fumes that turn a paper moistened with starch blue
• Salt (D): reddish-brown fumes that increase when copper turnings are added
Which is correct?
(2nd session 2022)

1. A (B) : a bromide salt , (C) : a nitrate salt.
2. B (A) : a chloride salt , (D) : an iodide salt.
3. C (D) : a nitrate salt , (C) : a bromide salt.
4. D (A) : a chloride salt , (D) : a nitrate salt.

The following reactions take place under suitable conditions:
Compounds (1), (2) and (3) are ..........
(1st session 2023)

1. A Compound (1): AgNO₃ , compound (2): HCl , compound (3): Na₂SO₃
2. B Compound (1): K₃PO₄ , compound (2): HBr , compound (3): Na₂S₂O₃
3. C Compound (1): AgNO₃ , compound (2): H₂SO₄ , compound (3): Na₂S₂O₃
4. D Compound (1): Na₃PO₄ , compound (2): HI , compound (3): Na₂SO₃

The anion that forms precipitates with both the cations (Ag⁺) and (Ba²⁺) is ..........
(2nd session 2021)

1. A Cl⁻
2. B HCO₃⁻
3. C NO₃⁻
4. D PO₄³⁻

You have solutions of two salts (A) and (B). When silver nitrate solution was added to each of them separately, it was observed that:
• a white precipitate that turns black on heating formed with the solution of salt (A).
• a white precipitate that dissolves in ammonia solution formed with the solution of salt (B).
The anions of salts (A) and (B) are ..........
(2nd session 2022)

1. A Anion of salt (A): Br⁻ , anion of salt (B): S₂O₃²⁻
2. B Anion of salt (A): SO₃²⁻ , anion of salt (B): Cl⁻
3. C Anion of salt (A): SO₃²⁻ , anion of salt (B): Br⁻
4. D Anion of salt (A): Cl⁻ , anion of salt (B): S₂O₃²⁻

If you have a mixture of BaSO₄ and Ba₃(PO₄)₂, which of the following is correct?
(Trial exam / June 2021)

1. A They can be separated from each other by adding dilute HCl and filtering.
2. B They can be separated from each other by adding water and filtering.
3. C BaSO₄ does not dissolve in water and dissolves in dilute HCl.
4. D Ba₃(PO₄)₂ dissolves in water and dissolves in dilute HCl.

You have the following pairs of salts:
(1) : sodium nitrite and sodium carbonate.
(2) : sodium sulphite and sodium sulphate.
(3) : potassium sulphate and potassium phosphate.
(4) : potassium iodide and copper sulphate.
For which of the previous pairs can dilute hydrochloric acid be used to distinguish between the two salts?
(Trial exam / May 2021)

1. A Pairs (1) , (3)
2. B Pairs (1) , (2)
3. C Pairs (3) , (4)
4. D Pairs (2) , (4)

Which of the following is used to distinguish between solid sodium sulphide and sodium sulphate?
(1st session 2021)

1. A AgNO₃(s)
2. B Ca(OH)₂(s)
3. C HCl(aq)
4. D NaOH(aq)

When dilute hydrochloric acid is added to three solid salts (A), (B) and (C) each separately, a gas is given off with (A), a gas is given off and a precipitate forms with (B), and no reaction takes place with (C).
The anions of (A), (B) and (C) are ..........
(2nd session 2021)

1. A Anion of salt (A): NO₂⁻ , anion of salt (B): S₂O₃²⁻ , anion of salt (C): SO₄²⁻
2. B Anion of salt (A): NO₃⁻ , anion of salt (B): S²⁻ , anion of salt (C): PO₄³⁻
3. C Anion of salt (A): Cl⁻ , anion of salt (B): S₂O₃²⁻ , anion of salt (C): SO₄²⁻
4. D Anion of salt (A): CO₃²⁻ , anion of salt (B): NO₃⁻ , anion of salt (C): PO₄³⁻

When AgNO₃ solution is added to solutions of the two salts (X) and (Y), a yellow precipitate forms in each of them, and when ammonia solution is added to the precipitates formed, the precipitate disappears with the solution of salt (Y) and stays as it is with the solution of salt (X).
Salts (X) and (Y) are ..........
(1st session 2021)

1. A Salt (X): NaI , salt (Y): Na₃PO₄
2. B Salt (X): NaCl , salt (Y): NaBr
3. C Salt (X): NaNO₃ , salt (Y): Na₂SO₄
4. D Salt (X): NaNO₂ , salt (Y): NaNO₃

Solution of salt (X) was added to each of three salt solutions (A), (B) and (C) separately, and the following formed:
• a white precipitate that turns black on heating with (A).
• a yellow precipitate that does not dissolve in ammonia solution with (B).
• a yellow precipitate that dissolves in ammonia solution with (C).
The anions of salts (A), (B) and (C) and reagent (X) are ..........
(1st session 2022)

1. A Reagent (X): AgNO₃ , anion (A): SO₃²⁻ , anion (B): PO₄³⁻ , anion (C): I⁻
2. B Reagent (X): KMnO₄ , anion (A): I⁻ , anion (B): SO₃²⁻ , anion (C): PO₄³⁻
3. C Reagent (X): Na₂S₄O₆ , anion (A): PO₄³⁻ , anion (B): Cl⁻ , anion (C): NO₃⁻
4. D Reagent (X): AgNO₃ , anion (A): SO₃²⁻ , anion (B): I⁻ , anion (C): PO₄³⁻

(A) and (B) are two solutions of potassium salts. Silver nitrate solution was added to each of them, and a yellow precipitate formed in each.
When dilute nitric acid was added to the two precipitates, the precipitate from solution (A) was found to dissolve in the acid, while the precipitate from solution (B) did not dissolve in the acid.
The anions of salts (A) and (B), respectively, are ..........
(Trial exam / May 2021)

1. A Anion of salt (A): phosphate , anion of salt (B): iodide
2. B Anion of salt (A): bromide , anion of salt (B): chloride
3. C Anion of salt (A): iodide , anion of salt (B): phosphate
4. D Anion of salt (A): chloride , anion of salt (B): iodide

When calcium chloride solution is added to solutions of the two salts (X) and (Y) in the cold, the solution of salt (X) forms a white precipitate, while no precipitate forms with the solution of salt (Y).
Salts (X) and (Y) are ..........
(1st session 2022)

1. A Salt (X): sodium carbonate , salt (Y): sodium bicarbonate.
2. B Salt (X): sodium nitrite , salt (Y): sodium thiosulphate.
3. C Salt (X): sodium chloride , salt (Y): sodium sulphite.
4. D Salt (X): sodium nitrite , salt (Y): sodium bicarbonate.

When dilute HCl is added to two salts (A) and (B) - each separately - a colourless, odourless gas is given off with salt (A), and a colourless gas that turns reddish-brown at the mouth of the tube is given off with salt (B).
The anions of salts (A) and (B) are ..........
(1st session 2022)

1. A Anion of salt (A): HCO₃⁻ , anion of salt (B): NO₃⁻
2. B Anion of salt (A): SO₃²⁻ , anion of salt (B): NO₃⁻
3. C Anion of salt (A): CO₃²⁻ , anion of salt (B): NO₂⁻
4. D Anion of salt (A): S²⁻ , anion of salt (B): NO₂⁻

When hot conc. sulphuric acid was added to salts (X), (Y) and (Z), the results were as follows:
• With salt (X): a colourless gas was given off.
• With salt (Y): fumes were given off that turn a paper moistened with starch yellow.
• With salt (Z): no observations appeared.
The anions of salts (X), (Y) and (Z) are ..........
(1st session 2022)

1. A Anion of salt (X): CO₃²⁻ , anion of salt (Y): Br⁻ , anion of salt (Z): I⁻
2. B Anion of salt (X): Br⁻ , anion of salt (Y): Cl⁻ , anion of salt (Z): PO₄³⁻
3. C Anion of salt (X): I⁻ , anion of salt (Y): Br⁻ , anion of salt (Z): Cl⁻
4. D Anion of salt (X): Cl⁻ , anion of salt (Y): Br⁻ , anion of salt (Z): SO₄²⁻

When dilute hydrochloric acid solution is added to two different salts - each separately - a gas is given off from each of them, and both gases can be oxidised.
The two salts are ..........
(Trial exam / March 2023)

1. A KHCO₃ , K₂S₂O₃
2. B KNO₂ , K₂S
3. C KNO₂ , K₂CO₃
4. D KNO₂ , K₂SO₃

Which of the following salts gives a mixture of gases with conc. sulphuric acid?
(1st session 2023)

1. A potassium carbonate.
2. B potassium phosphate.
3. C sodium chloride.
4. D sodium bromide.