Question

In Duma's method for estimation of nitrogen 0.3 g of an organic compound gave 50 mL of nitrogen collected at 300 K temperature and 715 mm pressure. Calculate the % composition of nitrogen in the compound: (Aqueous tension at 300 k = 15 mm)

Options

• 11.46%

• 17.46%

• 22.06%

• 39.65%

Answer 1

17.46%

Explanation:

Volume of nitrogen collected at 300 K and 715 mm pressure is 50 mL.

Actual pressure = 715 − 15 = 700 mm

Volume of nitrogen at STP = `(273 xx 700 xx 50)/(300 xx 760)` = 41.9 mL

22,400 ml of N at STP weights = 28 g

41.9 ml of nitrogen weights = `(28 xx 41.9)/22400 "g"`

% of nitrogen = `(28 xx 41.9 xx 100)/(22400 xx 0.3)` = 17.46%