1.突出基础知识例1 对于一定质量的理想气体,下述四个论述中正确的是( )(A)当分子热运动变剧烈时,压强必变大.(B)当分子热运动变剧烈时,压强可以不变.(C)当分子间的平均距离变大时,压强必变小.(D)当分子间的平均距离变大时,压强必变大. (2000年全国) 1. Outstanding basic knowledge Example 1 For a certain quality of ideal gas, the following four statements are correct () (A) When the molecular thermal motion becomes severe, the pressure must become greater. (B) When the molecular thermal motion becomes violent At that time, the pressure may not change. (C) When the average distance between molecules becomes larger, the pressure must become smaller. (D) When the average distance between molecules becomes larger, the pressure must increase. (Nationally in 2000)