题干

镍(Ni)是一种用途广泛的金属,常用于电镀工业和制造电池,硫酸镍溶液显绿色,氢氧化镍为难溶于水的绿色固体,在这些化合物中镍元素都显+2价.

(1)氢氧化镍的化学式为____ .

(2)将硫酸镍溶液加入试管中,再滴加足量氢氧化钠溶液,充分振荡后静置.

①反应的化学方程式为 ____ .

②预测反应现象:____ .

上一题 下一题 0.0难度 选择题 更新时间:2018-09-12 09:22:25

答案(点此获取答案解析)

Ni(OH)2,NiSO4+2NaOH═Ni(OH)2↓+Na2SO4,有绿色固体生成,溶液从绿色变成无色

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