幻灯片1高三化学课件_____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________幻灯片2第三节碱金属复习目标复习过程能力培养例题解析_____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________幻灯片3【复习目标】1、掌握碱金属元素性质的相似性和递变性2、学会碱金属离子的鉴别方法—焰色反应3、学会草木灰的提纯方法_____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________幻灯片4一、碱金属元素性质的相似性相似性1、原子最外层均为1个电子2、化合物中均显+1价，无气态氢化物，但能形成属离子化合物的氢化物如NaH，3、氧化物对应水化物为可溶性强碱，典型的活泼金属元素有强还原性4、均呈银白色（铯略带金色光泽），质软_____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________幻灯片5※注意：1、碱金属位于周期表第IA族，但IA族不全是碱金属元素如H2、同一周期中，碱金属原子半径（除惰性气体外）最大，金属性最强_____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________幻灯片6二、递变性LiNaKRbCs电子层数原子半径（离子）单质熔沸点单质密度增大增大升高增大※Na、K反常_____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________幻灯片7L