两种或两种以上物质均匀混合而彼此呈分子状态分布的物系称为溶液。溶液又可分为气态、固态和液态三种。通常所讲的溶液常指液态溶液而言。液态溶液又可分为电解质和非电解质溶液。本文将介绍非电解质溶液的一般理论。为简便起见,只讨论二组分的溶液,因为它是研究多组分体系的基础。 A system in which two or more substances are homogeneously mixed with each other in a molecular state is called a solution. The solution can be divided into gaseous, solid and liquid three. The usual solution is often referred to liquid solution. Liquid solution can be divided into electrolyte and non-electrolyte solution. This article will introduce the general theory of non-electrolyte solution. For the sake of simplicity, only the two-part solution will be discussed as it is the basis for the study of the multi-component system.