Question

某機場要用4500g溶質(zhì)質(zhì)量分數(shù)為2%的過氧乙酸溶液消毒，則需要用多少g溶質(zhì)質(zhì)量分數(shù)為15%的過氧乙酸來配制？同時需要水多少g？

Answer 1

分析：配制過程中溶質(zhì)質(zhì)量不變；由稀溶液的溶液質(zhì)量和溶質(zhì)質(zhì)量分數(shù)可以計算出溶質(zhì)質(zhì)量，由溶質(zhì)質(zhì)量和濃溶液的溶質(zhì)質(zhì)量分數(shù)可以計算出濃溶液的質(zhì)量．列出等式，解答即可．

解答：解：純過氧乙酸的質(zhì)量為：4500g×2%=90g
設需要質(zhì)量分數(shù)為15%過氧乙酸溶液的質(zhì)量為x，則
x×15%=90g
x=600g
需要水的質(zhì)量為：4500g-600g=3900g
答：需要用600g溶質(zhì)質(zhì)量分數(shù)為15%的過氧乙酸來配制，同時需要水的質(zhì)量為3900g

點評：本題主要考查溶質(zhì)質(zhì)量分數(shù)的計算、一定溶質(zhì)質(zhì)量分數(shù)的溶液的配置，難度較小．