<span>conductor because it conducts the electrons</span><span />
Since Group 2 alkali earth metals have 2 valence electrons, they tend to lose those 2 when forming ionic bonds. And the Loss of Electrons = Oxidation (L.E.O. for short). Therefore this group, including Mg and Ca, have an oxidation of [+2].
So the correct answer is C) +2
<span>the chemical equation will be Ni(OH)2(s)------>heat---> NiO(s) + H2O(g)
</span><span>we know that the heat supplied to decompose the compound.In the result the product H2O is assumed to be in the vapor state so that is gas.
hope it helps
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