Which of the following pair consists of only network solid?

Options

A. `SiO_(2), P_(4)O_(10)`
B. `P_(4)O_(10), SO_(3)`
C. `P_(3)O_(10), P_(4)O_(6)`
D. Diamond, `SiO_(2)`

Answer

To determine which of the following pairs consists of only network solids, we first need to understand what a network solid is. A network solid, also known as a covalent network solid, is a type of solid where atoms are bonded together by covalent bonds in a continuous network throughout the material. This means that there are no discrete molecules; instead, the entire solid is one large molecule.

### Step-by-Step Solution:

1. **Identify the Definition of Network Solids**:
- Network solids are characterized by a continuous network of covalent bonds. Examples include diamond and silicon dioxide (SiO2).

2. **Analyze Each Pair of Compounds**:
- We need to evaluate each pair of compounds given in the question to see if both compounds in the pair are network solids.

3. **Evaluate Diamond (C)**:
- Diamond is a well-known network solid. It consists of carbon atoms arranged in a tetrahedral structure, where each carbon atom is sp3 hybridized and covalently bonded to four other carbon atoms. This creates a three-dimensional network.

4. **Evaluate Silicon Dioxide (SiO2)**:
- Silicon dioxide (SiO2) is also a network solid. In SiO2, each silicon atom is covalently bonded to four oxygen atoms in a tetrahedral arrangement, forming a continuous three-dimensional network.

5. **Check Other Possible Pairs**:
- If there are other pairs given in the question, we need to check if they consist of network solids or not. For example, if one of the pairs includes metals or ionic compounds, they would not be classified as network solids.

6. **Conclusion**:
- After analyzing the pairs, we find that the only pair consisting of network solids is diamond and silicon dioxide (SiO2). Therefore, the correct answer is option four: diamond and SiO2.

### Final Answer:
The pair that consists of only network solids is **diamond and SiO2**.