0.1986 g of an organic substance when analysed by Duma's method give 32.96 ml of moist nitrogen measured at 14°C and 755 mm pressure. Calculate the percentage of nitrogen in the substance. (Aqueous tension at `14^@ `C = 12 mm)

Explanation

To calculate the percentage of nitrogen in the given organic substance using Duma's method, we can follow these steps:

### Step 1: Convert the volume of moist nitrogen to liters
Given:
- Volume of moist nitrogen (V₁) = 32.96 mL

To convert mL to liters:
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