Question

8g苛性鈉與一定質(zhì)量的稀鹽酸恰好完全反應(yīng)，所得溶液溶質(zhì)質(zhì)量分?jǐn)?shù)為26.5%，求所用稀鹽酸中溶質(zhì)的質(zhì)量分?jǐn)?shù)．

Answer 1

設(shè)生成的氯化鈉的質(zhì)量為x，所用的稀鹽酸中溶質(zhì)的質(zhì)量為y．
NaOH+HCl=NaCl+H₂O
40     36.5  58.5
8g     y       x

40

58.5

=

8g

x

  x=

58.5×8g

40

=11.7g
則生成的氯化鈉溶液的質(zhì)量為

11.7g

26.5%

=44.2g

40

36.5

=

8g

y

  y=

8g×36.5

40

=7.3g
則所用稀鹽酸中溶質(zhì)的質(zhì)量分?jǐn)?shù)為

7.3g

44.2g-8g

×100%=20.2%
答：所用稀鹽酸中溶質(zhì)的質(zhì)量分?jǐn)?shù)為20.2%．