Chapter 9.3, Problem 48PP

Interpretation Introduction

Interpretation:

The chemical, complete ionic and net ionic reaction between nitric acid with aqueous rubidium sulfide to form hydrogen sulfide gas needs to be determined.

Concept introduction:

The molecular equation of a chemical reaction represents the reactant and product molecules as their molecular formula. The physical states of substances should be written in parenthesis. The ionic equation can be written in which all aqueous substance must be written as their ions.

The net ionic equation is modified form of ionic equation in which the spectator ions must be cancelled from both sides.

Answer to Problem 48PP

Net ionic equation:

${\text{ 2 H}}_{{}_{}}^{\text{+}}\text{(aq})+{\text{ S}}_{}^{2-}\text{(aq)}\stackrel{}{\to }{\text{ H}}_{\text{2}}\text{S(g) }$

Explanation of Solution

Given information:

Reaction between nitric acid with aqueous rubidium sulfide forms hydrogen sulfide gas.

The molecular reaction equation between nitric acid with aqueous rubidium sulfide can be written as:

${\text{Rb}}_{\text{2}}{\text{S(aq) + 2 HNO}}_{\text{3}}\text{(aq)}\stackrel{}{\to }{\text{2 RbNO}}_{\text{3}}{\text{(aq) + H}}_{\text{2}}\text{S(g)}$

Since all compounds are in aqueous state so ionic equation must be:

${\text{2 Rb}}_{{}_{}}^{\text{+}}{\text{(aq) + S}}_{}^{2-}{\text{(aq) + 2 H}}_{{}_{}}^{\text{+}}\text{(aq})+{\text{2 NO}}_{{}_{\text{3}}}^{\text{-}}\text{(aq) }\stackrel{}{\to }{\text{2 Rb}}_{{}_{}}^{\text{+}}\text{(aq) }+{\text{2 NO}}_{{}_{\text{3}}}^{\text{-}}{\text{(aq) + H}}_{\text{2}}\text{S(g) }$

Here hydrogen sulfide is in gaseous state and Rb+ and NO₃- ions are spectator ions therefore the net ionic equation can be written as:

${\text{ 2 H}}_{{}_{}}^{\text{+}}\text{(aq})+{\text{ S}}_{}^{2-}\text{(aq)}\stackrel{}{\to }{\text{ H}}_{\text{2}}\text{S(g) }$

Conclusion

Net ionic equation:

${\text{ 2 H}}_{{}_{}}^{\text{+}}\text{(aq})+{\text{ S}}_{}^{2-}\text{(aq)}\stackrel{}{\to }{\text{ H}}_{\text{2}}\text{S(g) }$