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.

Explanation

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%`