Cyclic Hydrocarbons questions

Which molecular formula may represent a saturated cyclic compound?

1. A C₂H₄
2. B C₂H₂
3. C C₆H₁₄
4. D C₆H₁₂

In front of you are 4 cyclic hydrocarbon compounds:
Which order expresses the stability of these compounds?

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

Which of the following is correct?

1. A The bond angles in cyclic C₃H₆ are larger than in C₃H₈
2. B The general formula of cyclobutane differs from the general formula of butene.
3. C The boiling point of cyclobutane is higher than that of cyclopropane.
4. D Cyclopropane is more stable than cyclobutane.

Which of the following compounds needs the least energy to break its bonds?

1. A Propane.
2. B Cyclopropane.
3. C Hexane.
4. D Cyclohexane.

Which of the following compounds is the most stable and has the molecular formula C₆H₁₂?

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

What is the name of the compound that removes the colour of bromine dissolved in CCl₄ when it is passed through it?

1. A Butene.
2. B Cyclohexane.
3. C Pentane.
4. D Cyclopentane.

How many atoms are there in a molecule of the simplest cycloalkane?

1. A 8
2. B 9
3. C 10
4. D 12

From the opposite table:
Cyclopropane : 2091 kJ/mol
Cyclobutane : 2721 kJ/mol
Cyclopentane : 3291 kJ/mol
Cyclohexane : 3920 kJ/mol
We conclude that the heat of combustion of cycloalkanes ..........

1. A increases as the number of methyl and methylene groups in them increases.
2. B increases as the number of carbon atoms and methylene groups in them increases.
3. C decreases as the number of carbon atoms and methyl groups in them increases.
4. D decreases as the number of hydrogen atoms and methylene groups in them increases.

Which of the following describes three unbranched saturated cyclic compounds?

1. A Number of methyl groups in them: none , number of methylene groups in them: not equal
2. B Number of methyl groups in them: equal , number of methylene groups in them: none
3. C Number of methyl groups in them: not equal , number of methylene groups in them: none
4. D Number of methyl groups in them: none , number of methylene groups in them: equal

What is the IUPAC name of the opposite compound?

1. A 1-ethyl-3,3-dimethylcyclohexane.
2. B 3-ethyl-1,1-dimethylcyclohexane.
3. C 1,1-dimethyl-3-ethylcyclohexane.
4. D 1-ethyl-4,4-dimethylcyclohexane.

How many isomers does the molecular formula C₄H₈ have?

1. A 3
2. B 4
3. C 5
4. D 6

How many cycloalkane isomers have the molecular formula C₅H₁₀?

1. A 5
2. B 4
3. C 3
4. D 2

The catalytic thermal cracking of decane produced the simplest liquid alkane and compound (X).
How many cyclic isomers does compound (X) have?

1. A 2
2. B 3
3. C 4
4. D 5

The polymer shown in the opposite figure is prepared from a monomer.
Which of the following is an isomer of this monomer?

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

All of the following are correct for an isomer of the opposite compound (cyclopropene), except ..........

1. A It contains a triple covalent bond.
2. B It reacts with HBr according to Markovnikov's rule.
3. C It needs (1 mol) of hydrogen to saturate (1 mol) of it.
4. D Its catalytic hydration forms a ketone.

If the molecular formula of heptadecane is C₁₇H₃₆
What are the molecular formulas of normal hexadecane and cyclohexadecane, respectively?

1. A C₁₆H₃₄ / C₁₆H₃₀
2. B C₁₈H₃₈ / C₁₈H₃₆
3. C C₁₆H₃₄ / C₁₆H₃₂
4. D C₁₈H₃₈ / C₁₈H₃₄

1 g of a hydrocarbon burns completely, forming 3.22 g of carbon dioxide gas.
What is the name of this hydrocarbon? [C = 12 , H = 1 , O = 16]

1. A Cyclohexene.
2. B Cyclopentane.
3. C Ethene.
4. D Pentene.

Sodium acetate reacts with sodium hydroxide in the presence of calcium oxide, forming the organic gas (1) and the inorganic compound (2); and 1,3-dibromopropane reacts with sodium to form the cyclic organic compound (3) and 2 mol of NaBr
Which of the following describes compounds (1), (2) and (3)?

1. A Compound (1) is more reactive than compound (3) ✓ , compound (2) can be distinguished from sodium bromide by concentrated sulphuric acid ✓
2. B Compound (1) is more reactive than compound (3) ✗ , compound (2) can be distinguished from sodium bromide by concentrated sulphuric acid ✓
3. C Compound (1) is more reactive than compound (3) ✓ , compound (2) can be distinguished from sodium bromide by concentrated sulphuric acid ✗
4. D Compound (1) is more reactive than compound (3) ✗ , compound (2) can be distinguished from sodium bromide by concentrated sulphuric acid ✗

A student assumed the following in describing the opposite compound: CH₂C(CH₃)₂
(1) : the compound CH₃(CH)₂CH₃ is an isomer of it.
(2) : it reacts with hydrohalic acids according to Markovnikov's rule.
(3) : it is used as a monomer in addition polymerization.
(4) : cyclobutane is an isomer of it.
Which of the previous assumptions are correct?

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

From the following formulas:
Match each of the following to the previous formulas:
(1) 2-methylpropane.
(2) A compound with the molecular formula C₅H₁₂
(3) Two isomers.
(4) The compound that reacts with KMnO₄(aq) in an alkaline medium, forming a dihydric alcohol.

The molecular formula C₄H₈ has many structural formulas, including unbranched alkenes and cycloalkanes.
Draw the structural formulas of each of the following:
(1) the unbranched alkenes.
(2) the cycloalkanes.

The opposite figure shows the structural formula of compound (X):
(1) What is the structural formula of the unsaturated compound (Y) that is an isomer of compound (X)?
(2) Write the combustion equation of compound (X).

(A) and (B) are two organic compounds with the molecular formula C₃H₆:
(1) Draw the structural formula of compound (A), and write the IUPAC name of the compound produced by adding HBr to it.
(2) Draw the structural formula of compound (B). Why is this compound more reactive than the corresponding normal alkane?

Phenylethene is used as a monomer in addition polymerization:
(1) Draw the structural formula of this monomer.
(2) State 3 conditions needed to convert this monomer into a polymer.

The molecular formula C₅H₁₀ represents the following cyclic compounds:
• (X): contains no methyl groups.
• (Y): contains one methyl group.
• (Z): contains one methylene group.
Draw the structural formula of each of the three compounds, and write their IUPAC names.

When water is removed from propyl alcohol, compound (X) is produced. (Sample exam 2026)
Which of the following describes an isomer of compound (X)?

1. A Saturated, with 3 methyl groups.
2. B Unsaturated, with 3 methylene groups.
3. C Saturated and chemically reactive.
4. D Unsaturated and chemically reactive.

Which of the following compounds, when one mole of it burns completely, produces 5 mol of (CO₂) and 5 mol of water vapour? (Sample exam 2026)

1. A 2-methylbutane.
2. B 2,3-dimethyl-2-butene.
3. C 1,1-dimethylcyclopropane.
4. D 2-pentyne.

Which of the following is a saturated hydrocarbon that contains no methyl groups? (1st session 2021)

1. A C₅H₁₂
2. B C₆H₁₂
3. C C₇H₈
4. D C₇H₁₂

All of the following are correct for cyclohexane, except .......... (2nd session 2022)

1. A it is a saturated cyclic compound.
2. B it can be obtained from an aromatic compound.
3. C it is a stable alkane.
4. D its molecule contains 12 atoms.

The monomer of the opposite polymer is an isomer of the compound .......... (1st session 2023)

1. A cyclopropane.
2. B cyclobutane.
3. C propane.
4. D propene.

Using the following table: (Trial exam / June 2021)
(A) : C₂HBrClF₃ , (B) : CF₄ , (C) : CBr₂Cl₂ , (D) : C₅H₁₀
Which of the following choices is correct?

1. A (D) : a saturated cyclic compound , (A) : an alkane derivative.
2. B (B) : an alkene derivative , (C) : an alkane derivative.
3. C (C) : an alkyne derivative , (D) : an alkene derivative.
4. D (A) : an alkane derivative , (B) : an alkene derivative.

Which of the following properties of cyclobutane is correct? (2nd session 2021)

1. A It is less reactive than cyclopentane.
2. B It is more stable than normal pentane.
3. C It burns faster than cyclopentane.
4. D It burns more slowly than normal pentane.

The molecular formula (C₅H₁₀) represents three saturated aliphatic hydrocarbons, such that: (1st session 2023)
(A): contains no methyl groups.
(B): contains one methylene group.
(C): contains one methyl group.
The correct order of these compounds according to chemical reactivity is ..........

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

Which of the following compounds, when one mole of it burns in excess oxygen, gives 3 mol of water vapour and 3 mol of carbon dioxide? (Sample exam 2026)

1. A Propane.
2. B Cyclopropane.
3. C Propanol.
4. D Propyne.