??$解:(1\mathrm {)}實(shí)驗(yàn)3和實(shí)驗(yàn)4中反應(yīng)的碳酸鈣有剩余。$??
??$(2\mathrm {)}由實(shí)驗(yàn)3可知,\mathrm {m}為4.4。$??
??$(3\mathrm {)}設(shè)這種石灰石中碳酸鈣的質(zhì)量分?jǐn)?shù)是x。$??
??$\mathrm{CaCO}_3+2\mathrm{HCl}\xlongequal[]{ }\mathrm{CaCl}_2+\mathrm{H}_2\mathrm{O}+\mathrm{CO}_2↑$??
??$\mathrm{\frac {100 }{10g×x }=\frac {44 }{3.52g }~~~~~解得 x = 80% }$??
??$答:這種石灰石中碳酸鈣的質(zhì)量分?jǐn)?shù)為80\%。$??