9.0g of an ammonia solution is treated with 50ml 0.5N `H_(2)SO_(4)` solution,"20ml" of "0.1N" NaOH is required for back titration.What is the percentage of ammonia in the solution?

pH of when 50mL of 0.10 M ammonia solution is treated with 50 mL of 0.05 M HCI solution :- (pK_(b) "of ammonia"=4.74)

0.50 gm of an organic compound was treated according to Kjeldahl's meghod. The ammonia evolved was absorbed in 50 ml of 0.5 MH_2SO_4 . The residual acid required 60 ml of (M)/(2)NaOH solution. Find the percentage of nitrogen in the compound.