nitrogen atSTP (Letit be mL) PV T V Where p and V are the pressure and volume of nitrogen, p is different from the atmospheric pressure at which nitrogen gas is collected. The value of p is obtained by the relation; p = Atmospheric pressure – Aqueous tension 22400 mL N at STP weighs g. Fig. .
Estimation of carbon and hydrogen. Water and carbon dioxide formed on oxidation of substance are absorbed in anhydrous calcium chloride and potassium hydroxide solutions respectively contained in U tubes. mL N atSTP weighs g 22400 V V Percentage of nitrogen = 22400 V Problem . In Dumas’ method for estimation of nitrogen, .3g of an organic compound gave 50mL of nitrogen collected at 300K temperature and 715mm pressure.
Calculate the percentage composition of nitrogen in the compound. (Aqueous tension at 300K= mm) Volume of nitrogen collected at 300K and 715mm pressure is mL Actual pressure = - = mm Volumeof nitrogen atSTP .9mL , mL of N at STP weighs = g . .9mLof nitrogen weighs 22400 g