What is the general formula for the homologous series of alkenes?

• CnH2n

• CnH2n+2

• CnH2n-2

• CnH2n+1

Why are alkene molecules considered unsaturated?

• They are highly reactive with oxygen.

• They contain a triple carbon-carbon bond.

• They have more hydrogen atoms than alkanes.

• They contain a double carbon-carbon bond.

Which of the following is NOT one of the first four alkenes?

• Butene

• Propene

• Ethene

• Hexene

What functional group do alkenes contain?

• C=C

• C≡C

• –OH

• –COOH

Why do alkenes burn with smoky flames in air?

• Because they are saturated hydrocarbons.

• Due to their high boiling points.

• Because they contain oxygen.

• Due to incomplete combustion.

What happens to the double bond in alkenes during addition reactions?

• It forms a triple bond.

• It becomes a single carbon-carbon bond.

• It breaks completely.

• It remains unchanged.

Which of the following is a product of the addition reaction of alkenes with hydrogen?

• An alcohol

• A carboxylic acid

• An ester

• An alkane

What is the functional group of alcohols?

• C≡C

• –OH

• C=C

• –COOH

Which of the following is NOT one of the first four alcohols?

• Methanol

• Propanol

• Ethanol

• Hexanol

What happens when alcohols react with sodium?

• Hydrogen gas is produced.

• Carbon dioxide is released.

• Water is formed.

• A precipitate is formed.