（1）設(shè)6.0g石灰石樣品中CaCO₃的質(zhì)量為x．
           CaCO₃+2HCl═CaCl₂+H₂O+CO₂↑
            100                  44
             x                  2.2g
            

100

44

＝

x

2.2g

                x=5.0g
石灰石樣品中碳酸鈣的質(zhì)量分數(shù)為

5.0g

6.0g

×100%=83.3%
答：石灰石樣品中碳酸鈣的質(zhì)量分數(shù)為83.3%
（2）要求鹽酸溶液的質(zhì)量，必須知道鹽酸溶液溶質(zhì)的質(zhì)量分數(shù)和溶質(zhì)的質(zhì)量，而溶質(zhì)的質(zhì)量可根據(jù)化學(xué)方程式計算出，還需要知道鹽酸溶液中溶質(zhì)的質(zhì)量分數(shù)即可．
故答案為：稀鹽酸的溶質(zhì)質(zhì)量分數(shù)