`0.002 gm` of an organic compound was treated according to Kjeldahl's method. `0.2xx10^-4` mol of `H_2SO_4` was required to neutralise `NH_3`. Calculate the percentage of `N_2`.The percentage of `N_(2)` is `"7x%"` ,then `"x"` is

0.02gm of an organic compound was treated according to kjeldahl's method. 0.1xx10^(-4) mol of H_(2)SO_(4) was required to neutralise NH_(3) .The percentage of N_(2) is

0.04gm of an organic compound was treated according to Kjeldahl's method. 0.6xx10^(-3) mol of H_(2)SO_(4) was required to neutralise NH_(3) .What will be the percentage of N in the given organic compound?

Estimation of Nitrogen: There are two methods for the estimation of nitrogen (1) Dumas method and (2) Kjedahl's method. (1) Duma's method: A known mass of compound is heated with copper oxide (CuO) in an atmosphere of CO_(2) , which gives free nitrogen along with CO_(2) and H_(2)O . C_(x)H_(y)N_(z)+(2x+(y)/(2))CuO rarr xCO_(2) +(y)/(2)(H_(2)O)+(z)/(2)+(2x+(y)/(2))Cu. The gaseous mixture is passed over a heated copper gauze which converts traces of nitrogen oxides formed of N_(2) .The gaseous mixture is collected over an aqueous solution of KOH which absorbs CO_(2) and nitrogen is collected in the upper part of the graduated tube. (2) kjeldahl's method: A known mass of organic compound (0.5 gm) is mixed with K_(2)SO_(4) (10 gm) and CuSO_(4) (1.0 gm) or a drop of mercury (Hg) and conc. H_(2)SO_(4) (25 ml) , and heated in Kjeldahl's flask. CuSO_(4) or Hg acts as a catalyst , while K_(2)SO_(4) raises the boiling point of H_(2)SO_(4) . The nitrogen in the organic compound is quantitatively converted to ammonium sulphate . The resulting mixture is then distilled with excess of NaOH solution and the NH_(3) evolved is passes into a known but excess volume of standard HCl or H_(2)SO_(4) . The acid left unused is estimated by titration with some standard alkali . The amound of acid used against NH_(3) can thus be known and from this the percentage of nitogen is calculated. (a) C+H +S underset(H_(2)SO_(4))overset("conc.")rarr CO_(2) + H_(2)O +SO_(2) (b) N underset(H_(2)SO_(4))overset("conc.")rarr (NH_(4))_(2)SO_(4) (c) (NH_(4))_(2)SO_(4)+2NaOH rarr Na_(2)SO_(4)+2NH_(3) + 2H_(2)O (d) 2NH_(3) + H_(2)SO_(4) rarr (NH_(4))_(2)SO_(4) (3) This method is not applicable to compounds containing N in nitro and azo groups,and N persent in the ring (e.g., pyridine as N of these conpounds does not change to (NH_(4))_(2)SO_(4) (ammonium sulphate ) under these reaction condition. 0.002 gm of an organic compound was treated according to Kjeldahl's method . 0.2 xx 10^(-4) mol of H_(2)SO_(4) was required to neutralise NH_(3) . Calculated the percentage of N.

0.4 gm of an organic compound was treated according to Kjeldahl's method. The ammonia evoled was absorbed in 50 ml or 0.5MH_3PO_3 . The residual acid required 30 ml of 0.5MCa(OH)_2 Find the percentage of N_2 in the compound.

0.5 g of an organic compound cantaining N on Kjeldahlising required 29 ml of N/5 H_(2)SO_(4) for complete neutralization of NH3 . The percentage of N in the compound is

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.

0.5 g of an organic compound containing N on Kjeldahlising required 29 ml of N/5 H_(2)SO_(4) for complete neutrilization of NH_(3) . The percentage of N in the compound is