0.50 g of an organic compound was kjeldahlished. The ammonia evolved was passed in 50 cm^(3) of 1 N H_(2)SO_(4). The residual acid required 60 cm^(3) of N//2 NaOH solution. Calculate the pecentage of nitogen in the compound.

0.50 g of an organic compound was kjeldahlished. The ammonia evolved w

1.	0.50 g of an organic compound was kjeldahlished. The ammonia evolved was passed in 50 cm^(3) of 1 N H_(2)SO_(4). The residual acid required 60 cm^(3) of N//2 NaOH solution. Calculate the pecentage of nitogen in the compound.
Answer» Solution :Step I. calculation of volume of UNUSED acid Volume of `NaOH` solution required `=60 cm^(3)` Normality of `NaOH` solution `=1//2 N` Normality of `H_(2)SO_(4)` solution `= 1N` Volume of unused acid can be calculated by applying normality equation `ubrace(N_(1)V_(1))_("Acid")=ubrace(N_(1)V_(1))_("Base") 1xxV=1/2xx60=30 cm^(3)` Step II. Calculation of volume of acid used Volume of acid added `=50 cm^(3)` Volume of unused acid `=30 cm^(3)` Volume of acid used `=(50-30)=20 cm^(3)` Step III. Calculating of percentage of nitrogen MASS of compound `=0.50 g` Volume of acid used `=20 cm^(3)` Normality of acid used `= 1 N` PERSENTAGE of `N=(1.4xx"Volume of acid used"xx"Normality of acid used")/("Mass of the compound")` `=(1.4xx20xx1)/0.50=56%`