解：設(shè)樣品中硫酸銨的質(zhì)量為x
??$(\ \text {NH}_4)_2\ \text {SO}_4+2\ \text {NaOH}\xlongequal[\ \ \ \ \ \ ]{}\mathrm{Na_{2}SO_{4} } +2\ \text {H}_2\ \text {O}+2\ \text {NH}_3↑$??
132 34
x 1.7g
??$\mathrm{ \frac { 132 }{ 34 }=\frac { x }{ 1.7g } }$?? 解得 x = 6.6 g
化肥中硫酸銨的質(zhì)量分?jǐn)?shù)為 ??$\mathrm{\frac{6.6 g}{8.25 g}\times 100％= 80％}$??
氮元素的質(zhì)量分?jǐn)?shù)為 ??$\mathrm{\frac{ 6.6g×\frac{28}{132}}{ 8.25g}\times 100％=17 ％}$??
答：這種化肥中硫酸銨的質(zhì)量分?jǐn)?shù)是80%，氮元素的質(zhì)量分?jǐn)?shù)是17%。
