29.5 mg of an organic compound containing nitrogen was digested according to Kjeldahl's method and the evolved ammonia was absorbed in 20 ~mL of 0.1 M HCl solution. The excess of the acid required 15 ~mL of 0.1 M NaOH solution for complete neutralization. The percentage of nitrogen in the compound is

Step-by-step solution

Moles of HCl reacting with ammonia aligned & =( moles of HCl absorbed )-( moles of NaOH solution required) & = (20 0.1 10⁻³ )- (15 0.1 10⁻³ ) & = moles of NH ₃ evolved. & = moles of nitrogen in organic compound aligned aligned & wt. of nitrogen in org. comp =0.5 10⁻³ 14 & =7 10⁻³ ~g & % w t= 7 10⁻³ 29.5 10⁻³ =23.7 % & aligned