(i) Test for Nitrogen: Sodium fusion extract is boiled with iron sulphate and then acidified with concentrated sulphuric acid. A Prussian blue colour shows presence of nitrogen.
Test for Sulphur: Sodium fusion extract is acidified with acetic acid and then lead acetate is added. A black precipitate confirms presence of Sulphur.
(ii) Given, mass of CO2 = 0.506 g and mass of organic compound = 0.2 g.
% of Carbon = \(\frac{12\times mass\,of\,CO_2\times100}{44\times mass\,of\,organic\,compound}\)
= \(\frac{12\times0.506\times100}{44\times0.2}\)
= 2.76%