21. The reaction between an alcohol and a carboxylic acid to form an ester is known as:

a) Hydrolysis
b) Esterification
c) Oxidation
d) Reduction
Answer: b) Esterification

22. Which of the following compounds is a ketone?

a) Ethanol
b) Acetone
c) Acetic acid
d) Methanol
Answer: b) Acetone

23. The general formula for aldehydes is:

a) CnH2nC_nH_{2n}Cn​H2n​
b) CnH2n+1OC_nH_{2n+1}OCn​H2n+1​O
c) CnH2nOC_nH_{2n}\text{O}Cn​H2n​O
d) CnH2n+1CHOC_nH_{2n+1}CHOCn​H2n+1​CHO
Answer: d) CnH2n+1CHOC_nH_{2n+1}CHOCn​H2n+1​CHO

24. In organic chemistry, a “functional group” refers to:

a) A specific group of atoms responsible for the characteristic reactions of a compound
b) A group of carbon atoms
c) The overall shape of the molecule
d) The type of bond in the molecule
Answer: a) A specific group of atoms responsible for the characteristic reactions of a compound

25. The reaction where an alkene reacts with hydrogen in the presence of a catalyst is called:

a) Hydration
b) Hydrogenation
c) Halogenation
d) Dehydration
Answer: b) Hydrogenation

26. Which of the following is NOT a type of isomerism?

a) Structural isomerism
b) Geometric isomerism
c) Optical isomerism
d) Electronic isomerism
Answer: d) Electronic isomerism

27. The process of converting an alcohol into a ketone or aldehyde is called:

a) Reduction
b) Oxidation
c) Hydrolysis
d) Esterification
Answer: b) Oxidation

28. In the IUPAC naming system, the longest continuous chain of carbon atoms is used to determine:

a) The type of functional group
b) The position of double bonds
c) The root name of the compound
d) The type of reaction
Answer: c) The root name of the compound

29. The hydrocarbon with the formula C₆H₁₂ is:

a) Cyclohexane
b) Hexene
c) Hexane
d) Heptane
Answer: a) Cyclohexane

30. Which of the following is an example of a primary alcohol?

a) 2-Propanol
b) 1-Butanol
c) Cyclohexanol
d) 2-Butanol
Answer: b) 1-Butanol