已知A的质子数是x,B2-与A3+具有相同的电子层结构,则B元素的质子数为( ) 发布时间:2017-07-14 03:49 │ 来源:www.tikuol.com 题型:选择题 问题: 已知A的质子数是x,B2-与A3+具有相同的电子层结构,则B元素的质子数为( )A.x+5B.x-5C.x+1D.x-1
题型:选择题 Tom apologized for _____ to inform me of the change in the plan. [ ]A. his being not able B. his not being able C. him not to be D. him to be not able 查看答案