The percentage of nitrogen by mass in ammonium sulphate is closest to (atomic masses of H =1, N =14, O =16, S =32 )

Question

The percentage of nitrogen by mass in ammonium sulphate is closest to (atomic masses of H =1, N =14, O =16, S =32 ) (A) 21 % (B) 24 % (C) 36 % (D) 16 %

Tardigrade Admin · Accepted Answer

Total mass of ammonium sulphate ( NH 4)2 SO 4 =2 × 18+32+16 × 4 =36+96=132 Mass of nitrogen in ( NH 4)2 SO 4=28 % of N by mass in ( NH 4)2 SO 4=(28/132) × 100 =21.2 %

Q. The percentage of nitrogen by mass in ammonium sulphate is closest to (atomic masses of $H = 1, N = 14$ , $O = 16, S = 32$ )

$21%$

$24%$

$36%$

$16%$

Total mass of ammonium sulphate $(N H_{4})_{2} S O_{4}$
$= 2 \times 18 + 32 + 16 \times 4$
$= 36 + 96 = 132$
Mass of nitrogen in $(N H_{4})_{2} S O_{4} = 28$
$%$ of $N$ by mass in $(N H_{4})_{2} S O_{4} = \frac{28}{132} \times 100$
$= 21.2%$

Q. The percentage of nitrogen by mass in ammonium sulphate is closest to (atomic masses of H=1,N=14, O=16,S=32 )

21%

24%

36%

16%