Identify the compound that can not be Kjeldahlised

Which of the following fertilizers has the highest percentage of ‘N’

The Lassaigne’s extract is boiled with dill.$HN{O}_{3}HNO\_3$ before testing for halogens because

In the Kjeldahl’s method of estimation of ‘N’ present in a soil sample, ammonia evolved from 0.75g of sample, neutralized 10mL of 1 M $H_{2}S{O}_{4}H\_2SO\_4$. The % of ‘N’ in the soil is

31.7 mL of moist $N_{2}N\_2$ was obtained from 0.2033g of an organic compound in Duma’s method at $14^{\circ }C14^\backslash circ\; C$ and 758 mm pressure. If aq. tension at $14^{\circ }C=14mm14^\backslash circ\; C=\; 14mm$, the % of ‘N’ in the sample is

0.189g of substance, during Carius determination, gave 0.287g of AgCl. What is the % of chlorine in the sample

0.40g of an organic compound containing phosphorus gave 0.555g of $M{g}_2{P}_2{O}_{7}Mg\_2P\_2O\_7$ in Carius analysis. % of phosphorus in the organic compound is

A compound has C, H, N in the following percentage : C = 40%, H = 13.33%, N = 46.67%. What is its Empirical formula

1.89g of an organic compound containing C, H & O gave 2.64g $C{O}_{2}CO\_2$ and 1.08g $H_{2}OH\_2O$ upon combustion. Its Empirical formula is

When acetic acid and lead acetate are added to sodium extract during Lassaigne’s test, appearance of black precipitate shows the presence of