18= nB RT p V=V1+V2+. nB -OB n 或V=∑ B称为B的体积分数 V =nRT+RT 大. =a+历+) V=nR☑ Pe =PBPp n RT V B B = = B 或 V VB p nRT V = ( ) p RT n n p n RT p n RT V   = + + = + + 1 2 1 2 B B = B = n n V V p p V V x p p B B B B B B   = = = = B 称为B的体积分数 V = V1 + V2 + 