a) CH₄: Alkane - The presence of only carbon and hydrogen atoms with single bonds indicates an alkane.

b) C₂H₄: Alkene - The ratio of carbon and hydrogen suggests a double bond between carbon atoms, hence an alkene.

c) C₂H₅OH: Alcohol - The presence of a hydroxyl (-OH) group attached to a carbon atom indicates an alcohol.

d) CH₃COOH: Carboxylic acid - The presence of a carboxyl (-COOH) group indicates a carboxylic acid.

Answer 2

(a) Ethanoic acid:

Structure: CH₃COOH, Displayed: CH₃COOH

(b) Propanoic acid:

Structure: CH₃CH₂COOH, Displayed: CH₃CH₂COOH

(c) Butanoic acid:

Structure: CH₃CH₂CH₂COOH, Displayed: CH₃CH₂CH₂COOH

(d) Pentanoic acid:

Structure: CH₃CH₂CH₂CH₂COOH, Displayed: CH₃CH₂CH₂CH₂COOH

The reaction between a carboxylic acid and an alcohol to form an ester is a condensation reaction. It involves the reaction of a carboxylic acid (RCOOH) with an alcohol (R'OH) to produce an ester (RCOOR') and water (H₂O). An acid catalyst, typically sulfuric acid (H₂SO₄) or hydrochloric acid (HCl), is used to speed up the reaction. The acid catalyst protonates the carbonyl oxygen of the carboxylic acid, making it more susceptible to nucleophilic attack by the alcohol.

Reactants: Carboxylic acid (RCOOH) and Alcohol (R'OH)

Products: Ester (RCOOR') and Water (H₂O)

Role of Acid Catalyst: The acid catalyst protonates the carbonyl oxygen of the carboxylic acid, increasing the electrophilicity of the carbonyl carbon and facilitating the nucleophilic attack by the alcohol. This lowers the activation energy of the reaction, allowing it to proceed at a faster rate.

Balanced Chemical Equation: