On adding 1g arsenic to 80 g benzene, the freezing point of benzene is lowered by `0.213^(@)C`. The formula of arsenic molecule is : (Atomic mass of arsenic = 75) (`K_(f) = 5.12` K kg/mol)

Options

A. As
B. `AS_(2)`
C. `AS_(3)`
D. `AS_(4)`

Explanation

To solve the problem step by step, we will use the formula for depression in freezing point and the information provided in the question.

### Step 1: Identify the given data
- Mass of arsenic (WB) = 1 g
- Mass of benzene (WA) = 80 g
- Depression in freezing point (ΔTf) = 0.213 °C
- Freezing point depression constant for benzene (Kf) = 5.12 K kg/mol
- Atomic mass of arsenic = 75 g/mol
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