In Kjeldahl's method, the nitrogen present is estimated as-

1. N₂ 

2. NH₃

3. NO₂ 

4 None of the above

In the Kjeldahl's method for estimation of nitrogen present in a soil sample, ammonia evolved from 0.75 g of sample neutralised 10 mL of 1 M H₂SO₄. The percentage of nitrogen in the soil is

1. 37.33             2. 45.33

3. 35.33             4. 43.33

The Lassaigne's extract is boiled with a concentration HNO₃ while testing for halogens. By doing so it:

1. Helps in the precipitation of AgCl.

2. Increases the solubility product of AgCl.

3. Increases the concentration of NO₃^- ions.

4. Decomposes Na₂S and NaCN, if formed.

Ether and benzene can be separated by :-

(1) Filtration

(2) Distillation

(3) Crystallization

(4) Sublimation