A homologous series is a series of organic compounds which belong to the same family i.e., possess same functional group) and show similar chemical properties. The members of this series are called homologous and differ from each other by the number of `CH_2`, units in the main carbon chain.
The chemical properties of which of the following compounds is similar to the butane?

Options

A. Butyne
B. Propene
C. Propyne
D. Pentane

Answer

To determine which compound has similar chemical properties to butane, we first need to understand the characteristics of butane and its place in the homologous series.

### Step-by-Step Solution:

1. **Identify the Family of Butane**:
- Butane is an alkane, which is a type of hydrocarbon that contains only single bonds between carbon atoms. The general formula for alkanes is \( C_nH_{2n+2} \).

2. **Determine the Structure of Butane**:
- The molecular formula of butane is \( C_4H_{10} \). It consists of four carbon atoms and ten hydrogen atoms.

3. **Understand the Concept of Homologous Series**:
- A homologous series consists of compounds that have the same functional group and similar chemical properties. Members of the series differ by a \( CH_2 \) unit.

4. **Identify Possible Compounds**:
- We need to compare butane with other compounds to find one that is in the same homologous series (alkanes) and has a similar structure.

5. **Evaluate the Given Options**:
- If the options include compounds like pentane (\( C_5H_{12} \)), propane (\( C_3H_8 \)), butyne (\( C_4H_6 \)), and propene (\( C_3H_6 \)), we can analyze them:
- **Pentane**: \( C_5H_{12} \) (alkane, differs by one \( CH_2 \) unit from butane)
- **Propane**: \( C_3H_8 \) (alkane, differs by one \( CH_2 \) unit from butane)
- **Butyne**: \( C_4H_6 \) (alkyne, not in the same family)
- **Propene**: \( C_3H_6 \) (alkene, not in the same family)

6. **Conclusion**:
- The compounds that are similar to butane in chemical properties are those that are also alkanes. Thus, pentane and propane are both similar to butane, but since we are looking for the closest match in terms of the homologous series, **pentane** is the best answer because it is the next member in the series.

### Final Answer:
**Pentane** has similar chemical properties to butane.