Question

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

Answer 1

$\huge\underline{\fcolorbox{green}{pink}{Solution}}$

In Kjeldahl's method percentage of N is given by

${\boxed{\boxed{\sf \%N=\dfrac{1.4×Normality\:of\:acid×Volume\:of\:acid}{Weight\:of\: Compound}}}}$

$\implies{\sf 1M\:H_2SO_4=2NH_2SO_4}$

$\implies{\sf \% N=\dfrac{1.4×2×1}{0.75}}$

$\implies{\sf \red{\% N=37.33\% }}$