One can draw the map of a building on a glass plate by

Options

A. HI
B. HF
C. HBr
D. HCI

Answer

To solve the question "One can draw the map of a building on a glass plate by," we can follow these steps:

### Step 1: Understanding the Process
The process of drawing or creating designs on glass is known as etching. This involves using a chemical that can react with the glass surface to create a rough texture, allowing for designs to be made.

**Hint:** Think about what chemical processes can alter the surface of glass.

### Step 2: Identifying the Chemical Used
The chemical commonly used for etching glass is hydrogen fluoride (HF). This substance is effective because it reacts with the silicon dioxide (SiO2) present in glass.

**Hint:** Consider which halogen compounds might be used for etching due to their reactivity.

### Step 3: Understanding the Reaction
When HF is applied to glass, it reacts with SiO2 to produce silicon tetrafluoride (SiF2) and water (H2O). The reaction can be summarized as:
\[ \text{SiO}_2 + 4 \text{HF} \rightarrow \text{SiF}_4 + 2 \text{H}_2\text{O} \]

**Hint:** Recall the components of glass and how they interact with acids or bases.

### Step 4: Formation of Hydrofluorosilicic Acid
The silicon tetrafluoride (SiF2) can further react with HF to form hydrofluorosilicic acid (H2SiF6). This complex is formed when SiF2 interacts with more HF.

**Hint:** Think about how products of a reaction can lead to further reactions.

### Step 5: Conclusion
Thus, the answer to the question is that one can draw the map of a building on a glass plate by using hydrogen fluoride (HF).

**Final Answer:** The correct option is **B) HF**.

### Summary of Steps:
1. Understand the etching process.
2. Identify hydrogen fluoride as the chemical used.
3. Write the reaction between HF and SiO2.
4. Recognize the formation of hydrofluorosilicic acid.
5. Conclude with the answer.