Question 1

Which of the following is the correct general formula for linear (straight-chain) alkanes?

Accepted Answer

$C_nH_{2n+2}$

Question 2

What is the molecular formula for hexane?

Accepted Answer

$C_6H_{14}$

Question 3

Which of the following statements about isomers is TRUE?

Accepted Answer

Isomers have the same molecular formula but different arrangements of atoms.

Question 4

Which of the following is a constitutional isomer of butane ($C_4H_{10}$)?

Accepted Answer

2-methylpropane

Question 5

Given the alkane pentane ($C_5H_{12}$), how many constitutional isomers exist?

Accepted Answer

3

Question 6

Which of the following best describes a tertiary carbon atom?

Accepted Answer

A carbon attached to three other carbons

Question 7

What is the correct classification for a hydrogen atom attached to a secondary carbon?

Accepted Answer

Secondary hydrogen

Question 8

Which of the following molecules is NOT an alkane?

Accepted Answer

Propene

Question 9

If you have a model of $C_5H_{12}$, which of the following is NOT a valid constitutional isomer?

Accepted Answer

Cyclopentane

Question 10

Which of the following best explains why alkanes are considered saturated hydrocarbons?

Accepted Answer

They contain the maximum number of hydrogen atoms per carbon.

Question 11

Which of the following is the correct molecular formula for propane?

Accepted Answer

$C_3H_8$

Question 12

Which of the following is a correct example of a primary carbon atom?

Accepted Answer

A carbon in methane ($CH_4$)

Question 13

Which of the following is a correct example of a tertiary hydrogen atom?

Accepted Answer

A hydrogen attached to a carbon bonded to three other carbons

Question 14

Which of the following statements about structural isomers is FALSE?

Accepted Answer

They have identical physical properties.

Question 15

Which alkane has the molecular formula $C_4H_{10}$?

Accepted Answer

Butane

Question 16

Which of the following is a correct example of a secondary carbon atom?

Accepted Answer

A carbon attached to two other carbons

Question 17

Which of the following is a correct example of a secondary hydrogen atom?

Accepted Answer

A hydrogen attached to a carbon bonded to two other carbons

Question 18

Which of the following is NOT a property of alkanes?

Accepted Answer

They contain double bonds.

Question 19

Which of the following is the correct molecular formula for ethane?

Accepted Answer

$C_2H_6$

Question 20

Which of the following is a correct example of a branched alkane?

Accepted Answer

2-methylpropane

Alkanes: Structure, Isomerism, and Classification

Study Guide - Practice Questions