解将组分的质量分数换算成摩尔分数 20/32 =0.1233 0.8767 20/32+80/18 溶液的摩尔体积为 V=xV1+x2V2=0.1233×378+0.8767×18 =20.44cm3/mol解 将组分的质量分数换算成摩尔分数 0 1233 0 8767 20 32 80 18 20 32 1 2 . x . / / / x = = + = 溶液的摩尔体积为 . cm / mol V xV x V . . . 3 1 1 2 2 20 44 0 1233 37 8 0 8767 18 = = + =  + 