What can it be, if the precipitate of group I is soluble in hot water and insoluble in cold water?

Explanation

To determine what the precipitate of Group I could be, given that it is soluble in hot water and insoluble in cold water, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Group I Cations**:
- Group I cations in qualitative analysis typically include Ag^+, Pb^2+, and Hg2^2+.

2. **Consider the Solubility Characteristics**:
...