Glass reacts with HF forming:

Options

A. (A) `F_2`
B. (B) `H_2SiF_6`
C. (C) `CaF_2`
D. (D) `NaF`

Answer

To solve the question "Glass reacts with HF forming:", we need to analyze the reaction between glass and hydrogen fluoride (HF). The most common type of glass is silica glass, which has the chemical formula SiO2 (silicon dioxide).

### Step-by-Step Solution:

1. **Identify the Composition of Glass**:
- The main component of glass is silica, which is represented by the chemical formula SiO2.

2. **Understand the Reactant**:
- The reactant in this case is hydrogen fluoride (HF).

3. **Write the Reaction**:
- When SiO2 (glass) reacts with HF, the reaction can be represented as:
\[ \text{SiO}_2 + 4 \text{HF} \rightarrow \text{SiF}_4 + 2 \text{H}_2\text{O} \]
- Here, silicon tetrafluoride (SiF4) and water (H2O) are produced.

4. **Identify the Products**:
- From the reaction, we can see that the products formed are silicon tetrafluoride (SiF4) and water (H2O).

5. **Select the Correct Option**:
- The question asks for the products formed from the reaction. The correct answer based on the products formed is SiF4 (silicon tetrafluoride).

### Final Answer:
Glass reacts with HF forming SiF4 (silicon tetrafluoride) and H2O (water).