file:142铜、锌副族（二）.flv file:139氢和稀有气体（中）.flv file:107氮的氢化物（一）.flv file:31原子结构和元素周期律（二）.flv file:29反应速率与化学平衡（十二）.flv file:3化学基础知识（三）.flv file:150钛、钒副族与铬、锰副族.flv file:161铁系、铂系、钪、钇、镧系和锕系.flv