In the laboratory, for the preparation of dihydrogen gas form granular zinc, conc `H_(2)SO_(4)`,and `HNO_(3)` cannot be used. Why? Which is the most suitable acid?

Explanation

To answer the question regarding the preparation of dihydrogen gas from granular zinc, we need to analyze why concentrated sulfuric acid (H₂SO₄) and nitric acid (HNO₃) are not suitable for this reaction, and identify the most suitable acid for the preparation of hydrogen gas.

### Step-by-Step Solution:

1. **Understanding the Reaction with Concentrated Sulfuric Acid:**
- When zinc (Zn) reacts with concentrated sulfuric acid (H₂SO₄), the expected reaction would be:
\[
Zn + H_2SO_4 \rightarrow ZnSO_4 + H_2
...