Question # Nitrogen content in a sample of urea is ( 23.3 % . ) What is the percentage purity of urea in urea sample?

# Nitrogen content in a sample of urea is ( 23.3 % . ) What is the percentage purity of urea in urea sample?

(A) ( 90 % )

(B) ( 65 % )

(C) ( 50 % )

(D) ( 25 % )

Solution

Molecular mas ( =60 )

Mars of nitrogen ( =28 )

( % ) of ( N_{2} ) is ( 100 % )

( urea =100 times frac{28}{60}=46 cdot 67 )

Actueal ( %=23 cdot 3 )

( operatorname{Purl} y=frac{100 times 23 cdot 3}{46 cdot 67}=49 cdot 9 )