Question 1

Which of the following statements best explains why alkenes are classified as unsaturated hydrocarbons?

Accepted Answer

They contain at least one carbon-carbon double bond, allowing them to react with hydrogen to form alkanes.

Question 2

What is the correct IUPAC name for the compound with the condensed formula $$CH_3CH=CH_2$?

Accepted Answer

Propene

Question 3

Which of the following best describes the geometry and bond angles around each carbon in ethene ($$C_2H_4$$)?

Accepted Answer

Trigonal planar geometry with bond angles of $$120^\circ$$

Question 4

Which of the following compounds is an alkyne?

Accepted Answer

$$HC \equiv CH$$

Question 5

A student is asked to name the following compound: $$CH_3CH_2C \equiv CH. $$What is the correct IUPAC name?

Accepted Answer

1-butyne

Question 6

Which of the following is a correct statement about cis–trans isomerism in alkenes?

Accepted Answer

Cis–trans isomerism arises when each carbon of the double bond has two different groups attached.

Question 7

Which of the following best describes the difference between cis-2-butene and trans-2-butene?

Accepted Answer

Cis-2-butene has both methyl groups on the same side of the double bond, while trans-2-butene has them on opposite sides.

Question 8

Which of the following is the correct IUPAC name for the compound shown below?

$$\begin{array}{c}
	ext{CH}_3-CH=CH-CH_3$
\end{array}$$

Accepted Answer

2-butene

Question 9

A compound has the formula $$C_4H_6. $$Which of the following could be its structure?

Accepted Answer

Butyne

Question 10

Which of the following best explains why ethylene (ethene) is used to ripen bananas?

Accepted Answer

Ethylene is a plant hormone that accelerates the breakdown of cellulose, causing fruits to ripen.

Question 11

Which of the following is the correct IUPAC name for a ring structure with five carbons, a double bond, and a methyl group attached to carbon 3?

Accepted Answer

3-methylcyclopentene

Question 12

Which of the following is the correct order of steps for naming an alkene according to IUPAC rules?

Accepted Answer

Identify the longest carbon chain with the double bond, number the chain from the end nearest the double bond, name and locate substituents.

Question 13

Which of the following best describes the geometry around the carbon atoms in ethyne ($$C_2H_2$$)?

Accepted Answer

Linear geometry with bond angles of $$180^\circ$$

Question 14

Which of the following is a correct example of a cycloalkene?

Accepted Answer

Cyclopentene

Question 15

A compound is named trans-2-butene. Which of the following best describes its structure?

Accepted Answer

The two methyl groups are on opposite sides of the double bond.

Question 16

Which of the following is the correct condensed structural formula for propyne?

Accepted Answer

$$CH_3C \equiv CH$$

Question 17

Which of the following is a correct statement about the physical properties of cis and trans isomers?

Accepted Answer

Cis and trans isomers have different physical properties such as boiling points.

Question 18

Which of the following best describes the process of hydrogenation of an alkene?

Accepted Answer

Addition of hydrogen gas to an alkene to form an alkane.

Alkenes, Alkynes, and Isomers: Structure, Nomenclature, and Geometric Isomerism

Study Guide - Practice Questions