Organic Chemistry

What is crude oil primarily composed of?

• Only alkenes

• A single type of hydrocarbon

• A mixture of hydrocarbons

• Only alcohols

Answer explanation

Crude oil is primarily composed of a mixture of hydrocarbons, not just a single type. It contains various types of hydrocarbons such as alkanes, alkenes, and aromatics.

What is the general formula for alkanes?

• CnH2n+1OH

• CnH2n

• CnH2nO2

• CnH2n+2

Answer explanation

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

Which process is used to separate crude oil into fractions?

• Fractional distillation

• Evaporation

• Filtration

• Condensation

Answer explanation

Fractional distillation is the process used to separate crude oil into fractions based on their boiling points, allowing for the extraction of different components like gasoline, diesel, and kerosene.

What is the main purpose of cracking in the petrochemical industry?

• To convert alkenes into alkanes

• To remove impurities from crude oil

• To break down large alkanes into smaller ones

• To combine small alkanes into larger ones

Answer explanation

The main purpose of cracking in the petrochemical industry is to break down large alkanes into smaller ones, allowing for the production of more valuable products like gasoline and diesel.

What is the functional group of alcohols?

• COH

• CHO

• OH

• COOH

Answer explanation

The functional group of alcohols is OH, which consists of an oxygen atom bonded to a hydrogen atom. This group is what defines alcohols in organic chemistry.

Which of the following is a use of alcohols other than in drinks?

• As a fuel for cars

• As lubricants

• As solvents

• As a source of hydration

Answer explanation

Alcohols are commonly used as solvents in various industries, such as cleaning, pharmaceuticals, and cosmetics, making them a versatile choice beyond just being used in drinks.

What type of reaction is used to form esters?

• Oxidation

• Reduction

• Hydrolysis

• Condensation

Answer explanation

Esters are formed through a condensation reaction, where an alcohol and a carboxylic acid combine to eliminate water and form the ester functional group.

What is the result of the reaction between an alkene and bromine water?

• The solution becomes more concentrated

• The solution turns pink

• The solution becomes colorless

• The solution turns blue

Answer explanation

The solution becomes colorless because the alkene reacts with bromine water to form a colorless dibromoalkane product.

What is the main difference between addition and condensation polymerization?

• Addition polymerization can only occur with alkenes

• Condensation polymerization results in the loss of a small molecule like water

• Addition polymerization requires a catalyst, condensation does not

• Condensation polymerization cannot produce long-chain polymers

Answer explanation

Condensation polymerization results in the loss of a small molecule like water, distinguishing it from addition polymerization.

What is the general formula for carboxylic acids?

• COOH

• CnH2n+2

• CnH2n+1OH

• CnH2nO2

Answer explanation

The general formula for carboxylic acids is COOH, which represents the carboxyl functional group in the molecule.