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Is the entropy positive or negative in this question?

Which element is the least metallic between cadmium, silver, zinc, or iron?

Insoluble sulfide compounds are generally black in color. which of the following combinations could yield a black precipitate? check all that apply. na2s(aq)+kcl(aq) li2s(aq)+pb(no3)2(aq) pb(clo3)2(aq)+nano3(aq) agno3(aq)+kcl(aq) k2s(aq)+sn(no3)4(aq)

What is the formula of the ionic compound composed of calcium cations and chloride anions