Question

The ammonia evolved from the treatment of 0.30 g of an organic compound for the estimation of nitrogen was passed in 100 mL of 0.1 M sulphuric acid. The excess of acid required 20 mL of 0.5 M sodium hydroxide solution for complete neutralization. The organic compound is (a) urea (b) benzamide(c) acetamide (d) thiourea

Answer 1

Answer:

urea

H

2

SO

4

+2KOH→K

2

SO

4

+2H

2

O

1

M

1

V

1

(excess H

2

SO

4

)=

2

M

2

V

2

(KOH)

1

0.1×V

1

=

2

0.5×20

V

1

=50 mL

Volume of sulphuric acid used up to absorb NH

3

=50 mL

% N=

W

2.8×MV

=

0.3

2.8×0.1×50

=46.6

Thus, the organic compound will be urea, which has 46.6% nitrogen.