0.20 g of an anhydrous dibasic acid gave on combustion 0.040 g water and 0.195 g `CO_2`.0.5 g of its silver salt on ignition gave 0.355 g of silver. What is the molecular formula of the acid ?

Explanation

To determine the molecular formula of the anhydrous dibasic acid, we can follow these steps:

### Step 1: Calculate the moles of water and carbon dioxide produced from combustion.

1. **Moles of water (H₂O)**:
- Given mass of water = 0.040 g
- Molar mass of water (H₂O) = 18 g/mol
- Moles of water = mass / molar mass = 0.040 g / 18 g/mol = 0.00222 moles
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