Etching action of HF does not involve

Options

A. formation of `SiF_4.`
B. Corrosion of vessel wall.
C. formation of `H_2SiF_6.`
D. white marking on laboratory ware.

Answer

To solve the question regarding the etching action of HF (hydrofluoric acid), we need to analyze the options provided and determine which one does not involve the etching action of HF.

### Step-by-Step Solution:

1. **Understanding HF and its properties**: Hydrofluoric acid is known for its ability to etch glass and other silica-based materials. It reacts with silicon dioxide (SiO2) to form silicon tetrafluoride (SiF4), which is a gas.

2. **Analyzing the options**:
- **Option 1: Corrosion of vessel wall**: HF can corrode glass and certain metals, so this is involved in its etching action.
- **Option 2: Formation of Si2SIF6**: This option seems to be a typographical error, as Si2SIF6 is not a standard compound formed during the etching process. The correct compound related to the etching of glass by HF is SiF4.
- **Option 3: White marking on laboratory ware**: HF can leave white marks on glassware due to its etching action, so this is also involved.
- **Option 4: Formation of SiF4**: This is a well-known reaction when HF etches glass, so this is involved.

3. **Identifying the correct answer**: Based on the analysis, the option that does not involve the etching action of HF is the formation of Si2SIF6, as it is not a recognized product of the etching process.

### Conclusion:
The etching action of HF does not involve the formation of Si2SIF6.

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