Read the following and answer any four questions from (i) to (v).

A hydrocarbon (P) has the molecular formula C₁₀H₂₂ hydrocarbon (Q) has two carbon atoms less than (P) and belong to the same homologous series. A hydrocarbon (R) has two carbon atoms more than (P) and belong to the same homologous series.

(i) What is the molecular formula of (Q)?

1. C₁₂H₂₆
2. C₈H₁₆
3. C₈H₁₈
4. C₈H₁₄

(ii) To which homologous series do the compound (P), (Q) and (R) belong?

1. C_nH_2n
2. C₂H_2n-2
3. C_nH_2n+2
4. C_nH_2n+1

(iii) What is the molecular formula of (R)?

1. C₁₂H₂₆
2. C₁₂H₂₄
3. C₁₂H₂₂
4. C₁₂H₂₈

(iv) Identify the correct statement about compounds (P), (Q) and (R).

1. They have same melting and boiling points.
2. They have same chemical properties.
3. They have different general formula.
4. They differ by -CH unit.

(v) Compounds (P), (Q) and (R) are:

1. Alkanes. b. Alkenes.
2. Alkynes. d. None of these.