To clarify the relationship between the van der Hoff factor i and the number of ions per unit substance in the formula for reducing the freezing point of a strong electrolyte dilute solution ν.Freezing point depression experiments of 15 common strong electrolytes were performed and the value of i were calculated respectively.It was found that for different types of strong electrolytes,the value of i varies,mainly related to the number of charges carried by the positive and negative ions of the strong electrolyte and their nature.The i of the 1-1(positively and negatively charged)type strong electrolyte is close to 2,while the difference between i and ν is significant as for the other types of strong electrolytes,especially for type 2-2 sulfates.The order of deviation from maximum to minimum is:type 2-2、type 3-1、type 1-2、type 1-1.This result provides an experimental basis for the valueof i in the formula for freezing point depression of strong electrolyte dilute solutions,and provides a reference for exploratory experiments on ffreezing point depression.
关键词
强电解质稀溶液/凝固点降低/范特霍夫系数/探究性实验
Key words
strong electrolyte dilute solution/the freezing point depression/Van Der Hoff coefficient/exploratory experiment
维普
万方数据