Final answer:
Combining rubidium bromide with calcium sulfide does not yield a reaction because they do not form an insoluble product according to solubility rules, resulting in no reaction.
Step-by-step explanation:
When rubidium bromide (RbBr) and calcium sulfide (CaS) are combined in a reaction, we must consider the solubility rules to determine if a reaction occurs. Both rubidium compounds and calcium compounds are generally soluble in water, and neither bromide ions nor sulfide ions would result in an insoluble product with these particular cations. Therefore, no precipitation reaction would take place, and the correct chemical equation response is noreaction.
The chemical equation for the reaction between rubidium bromide and calcium sulfide is:
RbBr(aq) + CaS(aq) → Rb2S(aq) + CaBr2(aq)
The phases of the reactants and products in the equation are:
RbBr(aq) - aqueous CaS(aq) - aqueous Rb2S(aq) - aqueous CaBr2(aq) - aqueous
So, the complete balanced chemical equation with the phases is:
RbBr(aq) + CaS(aq) → Rb2S(aq) + CaBr2(aq).