Hydrocarbons Practice Questions

Class 11 · Chemistry · 1996 free MCQs with instant results and detailed explanations.

1996

Total

655

Easy

966

Medium

375

Hard

Start Practicing Hydrocarbons

Take a timed quiz or customize your practice session

Quick Quiz (10 Qs) → Mock Test (25 Qs) ⚙ Customize

Topics in Hydrocarbons

Alkanes 528

Aromatic Hydrocarbons 541

Alkenes 508

Alkynes 419

Sample Questions from Hydrocarbons

Here are 10 sample questions. Start a quiz to get randomized questions with scoring.

Easy

Which of the following is a saturated hydrocarbon?

A. Pentane

B. Butene

C. Benzene

D. Cyclohexene

Show Answer & Explanation

Correct Answer: A

Pentane is a saturated hydrocarbon, meaning it has single bonds only between carbon atoms. Others contain double or ring structures.

Easy

What is the molecular formula for octane?

A. C8H18

B. C7H16

C. C8H16

D. C9H20

Show Answer & Explanation

Correct Answer: A

Octane is an alkane with eight carbon atoms and follows the general formula CnH2n+2, resulting in C8H18.

Easy

Which of the following properties increases with the increasing chain length of alkanes?

A. Boiling Point

B. Solubility in water

C. Density compared to water

D. Flammability

Show Answer & Explanation

Correct Answer: A

The boiling point of alkanes increases with chain length due to greater van der Waals forces, while solubility in water decreases.

Medium

Which of the following alkanes has the highest boiling point?

A. Pentane

B. Butane

C. Hexane

D. Decane

Show Answer & Explanation

Correct Answer: D

Decane has the highest boiling point due to its larger molecular size and surface area, which increases van der Waals forces.

Medium

What is the general formula for alkanes?

A. CₙH₂ₙ₊₂

B. CₙH₂ₙ₋₂

C. CₙH₂ₙ

D. CₙH₂ₙ₊₄

Show Answer & Explanation

Correct Answer: A

The general formula for alkanes is CₙH₂ₙ₊₂, where n is the number of carbon atoms.

Medium

Which of the following is a branched-chain alkane?

A. Butane

B. Hexane

C. Isobutane

D. Octane

Show Answer & Explanation

Correct Answer: C

Isobutane has a branched structure, whereas the others are straight-chain alkanes.

Medium

Which alkane is expected to be a gas at room temperature?

A. Butane

B. Octane

C. Hexadecane

D. Decane

Show Answer & Explanation

Correct Answer: A

Butane has a lower molecular weight and is a gas at room temperature, while the others are liquids or solids.

Hard

Which of the following alkanes is a branched-chain hydrocarbon?

A. Butane

B. Hexane

C. Isobutane

D. Decane

Show Answer & Explanation

Correct Answer: C

Isobutane (or methylpropane) has a branched structure, unlike the straight-chain alkanes listed.

Hard

What is the IUPAC name for the alkane with the formula C8H18?

A. Octane

B. Heptane

C. Nonane

D. Decane

Show Answer & Explanation

Correct Answer: A

The alkane C8H18 is known as octane, which follows the formula CnH2n+2 for n=8.

Q10

Hard

What is the angle between the hydrogen atoms in an alkane molecule?

A. 90 degrees

B. 120 degrees

C. 109.5 degrees

D. 180 degrees

Show Answer & Explanation

Correct Answer: C

Alkanes have a tetrahedral geometry around each carbon atom, resulting in bond angles of about 109.5 degrees.

Showing 10 of 1996 questions. Start a quiz to practice all questions with scoring and timer.

Practice All 1996 Questions →

More Chemistry Chapters

1 Some Basic Concepts of Chemistry

901 Qs →

2 Structure of Atom

1867 Qs →

3 Classification of Elements and Periodicity

1856 Qs →

4 Chemical Bonding and Molecular Structure

2034 Qs →

1897 Qs →

1764 Qs →

1739 Qs →

1677 Qs →

Other Class 11 Subjects

📐 Mathematics → ⚡ Physics → 🧬 Biology →

Hydrocarbons — Class 11 Chemistry Practice Questions Online

This page contains 1996 practice MCQs for the chapter Hydrocarbons in Class 11 Chemistry. The questions are organized by difficulty — 655 easy, 966 medium, 375 hard — so you can choose the right level for your preparation.

Every question includes a detailed explanation to help you understand the concept, not just memorize answers. Take a timed quiz to simulate exam conditions, or practice at your own pace with no time limit. This chapter covers 4 topics, giving you comprehensive coverage of the entire chapter.