用两种不同浓度的溶液配制所需一种新浓度溶液时,用“十字交叉法”比用代数法求解简捷实用。因此在教科书中、在化工、医学等方面得到广泛应用。以前教本上介绍的“十字交叉法”,在教学中学生仍感困难,我们作了些改变,经过三年来的实践,学生觉得易于掌握。下面对这种方法作一些说明: 一、原来的“十字交叉法”图式 With two different concentrations of solution preparation of a new concentration required solution, the use of “cross method” than using algebraic method to solve simple and practical. Therefore, in textbooks, in the chemical, medical and other aspects of a wide range of applications. In the past, the “Cross-Crossing Method” introduced in the textbooks still impacted students in teaching. We made some changes. After three years of practice, students feel that they are easy to grasp. Here's some explanation of this method: First, the original “cross” method