题型:名词解释 Everyone dose something for ______ purpose; there is no such ______ person who dose things fornothing in the world.[ ]A. a; a B. a;/ C. the; a D. the; / 查看答案
题型:名词解释 元素R的气态氢化物化学式为HxR.在标准状况下,8.5gHxR气体的体积是5.6L。将5. 1gHxR气体通入200ml 0.75mol/L的CuCl2溶液中正好完全反应,并生成黑色沉淀(1)求HxR的相对分子质量;(2)推断x值,并确定R元素的名称. 查看答案