一份溶質(zhì)的質(zhì)量分?jǐn)?shù)為2%的氯化鈉溶液蒸發(fā)掉40g水后,其溶質(zhì)的質(zhì)量分?jǐn)?shù)變?yōu)閘0%,則原溶液中溶質(zhì)的質(zhì)量為( )
A. 1g
B. 2g
C. 5g
D. 8g
一份溶質(zhì)的質(zhì)量分?jǐn)?shù)為2%的氯化鈉溶液蒸發(fā)掉40g水后,其溶質(zhì)的質(zhì)量分?jǐn)?shù)變?yōu)閘0%,設(shè)原溶液的質(zhì)量為x,則
×100%=10% x=50g
則原溶液中溶質(zhì)的質(zhì)量為50g×2%=1g.
故選A.