Which of the following is non-polar molecular solid?

Options

A. SiC
B. Naphthlene
C. HCl
D. AIN

Answer

To determine which of the following is a non-polar molecular solid, we need to analyze the given options.

1. **Understanding Molecular Solids**: Molecular solids are composed of molecules held together by intermolecular forces. These forces can be weak (like van der Waals forces) or strong (like hydrogen bonds). The polarity of the molecules plays a crucial role in the type of solid formed.

2. **Identifying Non-Polar Molecules**: Non-polar molecules have an even distribution of electron density, which means they do not have distinct positive and negative ends. Examples of non-polar molecules include hydrocarbons like naphthalene.

3. **Analyzing the Options**:
- If one of the options is naphthalene (C10H8), we recognize that it is a hydrocarbon and thus non-polar.
- If another option is HCl (hydrochloric acid), we know that HCl is a polar molecule due to the difference in electronegativity between hydrogen and chlorine.

4. **Conclusion**: Since naphthalene is non-polar and HCl is polar, the correct answer to the question "Which of the following is a non-polar molecular solid?" is naphthalene.

### Step-by-Step Solution:
1. **Identify the nature of the solids**: Determine if the options provided are molecular solids.
2. **Check the polarity of each option**: Assess whether each solid is polar or non-polar.
3. **Select the non-polar molecular solid**: Choose the option that is identified as non-polar.