Question

將10g36%的濃鹽酸稀釋成15%的稀鹽酸，需加水的質(zhì)量是

1. A.
   11g
2. B.
   13g
3. C.
   14g
4. D.
   16g

Answer 1

C
分析：根據(jù)加水稀釋前后溶液中溶質(zhì)質(zhì)量不變，即10g36%的濃鹽酸中所含HCl的質(zhì)量與稀釋所得15%的稀鹽酸中所含HCl的質(zhì)量相等，據(jù)此可計(jì)算需要加水的質(zhì)量．
解答：
設(shè)需要加水的質(zhì)量為x
10g×36%=（10g+x）×15%
x=14g
故選C．
點(diǎn)評(píng)：加水稀釋時(shí)，稀釋前溶液的質(zhì)量×溶液中溶質(zhì)的質(zhì)量分?jǐn)?shù)=稀釋后溶液的質(zhì)量×溶液中溶質(zhì)的質(zhì)量分?jǐn)?shù)．