Name two poisonous gases which can be prepared from chlorine gas.

Explanation

To answer the question about two poisonous gases that can be prepared from chlorine gas, we can follow these steps:

### Step 1: Identify the Gases
The two poisonous gases that can be prepared from chlorine gas are:
1. Phosgene (COCl₂)
2. Mustard gas (ClCH₂CH₂)₂S

### Step 2: Preparation of Phosgene
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