Question

 將11g含少量雜質(zhì)（雜質(zhì)不溶于水，也不溶于酸）的碳酸鈣固體，加入到43.8g鹽酸溶液中，恰好完全反應(yīng)，產(chǎn)生CO₂氣體4.4g。請計(jì)算：原固體中碳酸鈣質(zhì)量分?jǐn)?shù)。（結(jié)果保留一位小數(shù)）

Answer 1

解：設(shè)原固體中碳酸鈣的質(zhì)量為x

   CaCO₃ + 2HCl==CaCl₂ + H₂O+CO₂↑................................1分

100                                                                                         44

X                           4.4g................................1分

100/44=x/4.4g.....................................................................1分

X=10g...................................................................................1分

10g/11g≈90.9%.......................................1分

答：原固體中碳酸鈣的質(zhì)量分?jǐn)?shù)為90.9%