Name the three chlorides which are insoluble in dilute `HCl`.name one chloride, which is soluble in hot water but insoluble in cold water.

Explanation

To solve the question, we need to identify three chlorides that are insoluble in dilute hydrochloric acid (HCl) and one chloride that is soluble in hot water but insoluble in cold water.

### Step-by-Step Solution:

1. **Identify Chlorides Insoluble in Dilute HCl:**
- To determine which chlorides are insoluble in dilute HCl, we need to consider the reactivity of the metals in the chlorides. Metals that are less reactive than hydrogen (which is present in HCl) will not react with it and their chlorides will remain insoluble.
- The metals that are less reactive than hydrogen in the reactivity series include Lead (Pb), Silver (Ag), and Mercury (Hg).

...