How many of the following compounds from HCl on hydrolysis as one of the products (major or minor)
(i)`BCl_3` , (ii)`BiCl_3` , (iii)`SO_2Cl_2` (iv)`NCl_3` (v)`PCl_5` (vi)`CrO_2Cl_2` (vii)`CH_3Cl` (viii)NaCl

Answer

To determine how many of the given compounds form HCl on hydrolysis, we will analyze each compound one by one:

1. **BCl₃ (Boron Trichloride)**:
- Hydrolysis Reaction:
\[ BCl_3 + 3H_2O \rightarrow H_3BO_3 + 3HCl \]
- **HCl is formed**.

2. **BiCl₃ (Bismuth Trichloride)**:
- Hydrolysis Reaction:
\[ BiCl_3 + 3H_2O \rightarrow BiOCl + 2HCl \]
- **HCl is formed**.

3. **SO₂Cl₂ (Sulfuryl Chloride)**:
- Hydrolysis Reaction:
\[ SO_2Cl_2 + 2H_2O \rightarrow H_2SO_4 + 2HCl \]
- **HCl is formed**.

4. **NCl₃ (Nitrogen Trichloride)**:
- Hydrolysis Reaction:
\[ NCl_3 + 3H_2O \rightarrow NH_3 + 3HCl \]
- **HCl is formed**.

5. **PCl₅ (Phosphorus Pentachloride)**:
- Hydrolysis Reaction:
\[ PCl_5 + 4H_2O \rightarrow H_3PO_4 + 5HCl \]
- **HCl is formed**.

6. **CrO₂Cl₂ (Chromyl Chloride)**:
- Hydrolysis Reaction:
\[ CrO_2Cl_2 + 2H_2O \rightarrow H_2CrO_4 + 2HCl \]
- **HCl is formed**.

7. **CH₃Cl (Chloromethane)**:
- Hydrolysis Reaction:
\[ CH_3Cl + H_2O \rightarrow CH_3OH + HCl \]
- **HCl is formed**.

8. **NaCl (Sodium Chloride)**:
- Hydrolysis Reaction:
\[ NaCl + H_2O \rightarrow NaOH + HCl \]
- **HCl is formed**.

Now, let's summarize the results:
- Compounds that form HCl on hydrolysis: BCl₃, BiCl₃, SO₂Cl₂, NCl₃, PCl₅, CrO₂Cl₂, CH₃Cl, NaCl.

Thus, **7 compounds** from the list form HCl on hydrolysis.

### Final Answer:
**7 compounds form HCl on hydrolysis.**