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Following Kjeldahl's method, 1 g of organic compound released ammonia, that neutralised 10 mL of 2 M H2SO4. The percentage of nitrogen in the compound is %.
56
2NH3 + H2SO4 (NH4)2SO4
mmol of H2SO4 = 10 × 2 = 20 ⇒ mmol of NH3 = 2 × 20 = 40 = mmol of N
Mass of N = 40 × 10-3 × 14 = 0.56 g
∴ % N = 0.561 × 100 = 56%
Answer: 56
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