Which of the following alkane is not liquid at room temperature?

Options

A. `C_(5)H_(12)`
B. `C_(17)H_(36)`
C. `C_(10)H_(22)`
D. `C_(4)H_(10)`

Answer

To determine which alkane is not liquid at room temperature, we can analyze the properties of alkanes based on their molecular weight and the number of carbon atoms they contain.

### Step-by-step Solution:

1. **Understanding Alkanes**: Alkanes are hydrocarbons consisting only of carbon (C) and hydrogen (H) atoms, with single bonds between them. They can exist in different states (gaseous, liquid, solid) depending on their molecular weight and structure.

2. **Classification by Carbon Atoms**:
- Alkanes with **1 to 4 carbon atoms** (e.g., methane, ethane, propane, butane) are typically gases at room temperature.
- Alkanes with **5 to 17 carbon atoms** are generally liquids at room temperature.
- Alkanes with **more than 17 or 18 carbon atoms** are usually solids at room temperature.

3. **Identifying the Alkane in Question**: We need to identify which alkane from the given options has 4 or fewer carbon atoms, as these will be gaseous at room temperature.

4. **Conclusion**: Since alkanes with 1 to 4 carbon atoms are gases, any alkane in this range will not be liquid at room temperature. Therefore, if we consider the alkane with 4 carbon atoms (butane), it will be the one that is not liquid at room temperature.

### Final Answer:
The alkane that is not liquid at room temperature is **butane (C4H10)**.