Question

13克Zn與100克稀硫酸恰好完全反應(yīng)，求反應(yīng)后所得溶液中溶質(zhì)的質(zhì)量分?jǐn)?shù)．________．

Answer 1

28.6%
分析：要求所得溶液的溶質(zhì)質(zhì)量分?jǐn)?shù)，需要求出溶質(zhì)的質(zhì)量和溶液的質(zhì)量，根據(jù)信譽(yù)硫酸的反應(yīng)求出生成硫酸鋅和氫氣的質(zhì)量．
解答：設(shè)生成硫酸鋅的質(zhì)量為x，生成氫氣的質(zhì)量為y
Zn+H₂SO₄═ZnSO₄+H₂↑
65 161 2
13g x y
=
x=32.2g
=
y=0.4g
反應(yīng)后所得溶液中溶質(zhì)的質(zhì)量分?jǐn)?shù)為：×100%=28.6%．
答：反應(yīng)后所得溶液中溶質(zhì)的質(zhì)量分?jǐn)?shù)為為28.6%．
點(diǎn)評(píng)：本題考查了根據(jù)化學(xué)方程式的計(jì)算，完成此題，可以依據(jù)題干提供的信息結(jié)合溶質(zhì)質(zhì)量分?jǐn)?shù)公式進(jìn)行．