Question

write the net ionic equation, including the phases.
2HBr(aq)+Ba(OH)2(aq) ---> 2H2O(l)+BaBr2(aq)

Answer 1

Concepts and reason

The net ionic equation is a chemical equation which shows only the chemical species involved in the reaction. Based on the solubility rule, strong electrolytes dissociate completely in an aqueous solution. The net ionic equation can be written with the help of a balanced chemical equation.

Fundamentals

• Solubility: Solubility is the ability of a substance (solute) to dissolve in a solvent. Strong acids and strong bases dissociate completely and forms ions. An aqueous substance only dissociates into ions.

• Balanced chemical equation: According to the law of conservation of mass, mass is neither created nor destroyed. This means that in a balanced chemical equation, the number of atoms present in the reactant side and product side should be the same.

• Spectator ions: Spectator ions are ions that are common on both sides of the reaction equation. This means that the ions in the reactant side as well as the product side are the same.

The given balanced chemical equation is

${\rm{2HBr}}\left( {{\rm{aq}}} \right){\rm{ + Ba}}{\left( {{\rm{OH}}} \right)_{\rm{2}}}\left( {{\rm{aq}}} \right)\longrightarrow{{}}{\rm{2}}{{\rm{H}}_{\rm{2}}}{\rm{O}}\left( {\rm{l}} \right){\rm{ + BaB}}{{\rm{r}}_{\rm{2}}}\left( {{\rm{aq}}} \right)$

From the balanced equation, it is observed that barium hydroxide reacts with hydro bromic acid to form barium bromide and water as products.

The ionic equation for the balanced chemical equation is

${\rm{2}}{{\rm{H}}^{\rm{ + }}}\left( {{\rm{aq}}} \right){\rm{ + 2B}}{{\rm{r}}^{\rm{ - }}}\left( {{\rm{aq}}} \right){\rm{ + B}}{{\rm{a}}^{{\rm{2 + }}}}\left( {{\rm{aq}}} \right){\rm{ + 2O}}{{\rm{H}}^{\rm{ - }}}\left( {{\rm{aq}}} \right)\longrightarrow{{}}{\rm{2}}{{\rm{H}}_{\rm{2}}}{\rm{O}}\left( {\rm{l}} \right){\rm{ + B}}{{\rm{a}}^{{\rm{2 + }}}}\left( {{\rm{aq}}} \right){\rm{ + 2B}}{{\rm{r}}^{\rm{ - }}}\left( {{\rm{aq}}} \right)$

The given balanced chemical equation is

${\rm{2HBr}}\left( {{\rm{aq}}} \right){\rm{ + Ba}}{\left( {{\rm{OH}}} \right)_{\rm{2}}}\left( {{\rm{aq}}} \right)\longrightarrow{{}}{\rm{2}}{{\rm{H}}_{\rm{2}}}{\rm{O}}\left( {\rm{l}} \right){\rm{ + BaB}}{{\rm{r}}_{\rm{2}}}\left( {{\rm{aq}}} \right)$

The ionic equation for this reaction is

${\rm{2}}{{\rm{H}}^{\rm{ + }}}\left( {{\rm{aq}}} \right){\rm{ + 2B}}{{\rm{r}}^{\rm{ - }}}\left( {{\rm{aq}}} \right){\rm{ + B}}{{\rm{a}}^{{\rm{2 + }}}}\left( {{\rm{aq}}} \right){\rm{ + 2O}}{{\rm{H}}^{\rm{ - }}}\left( {{\rm{aq}}} \right)\longrightarrow{{}}{\rm{2}}{{\rm{H}}_{\rm{2}}}{\rm{O}}\left( {\rm{l}} \right){\rm{ + B}}{{\rm{a}}^{{\rm{2 + }}}}\left( {{\rm{aq}}} \right){\rm{ + 2B}}{{\rm{r}}^{\rm{ - }}}\left( {{\rm{aq}}} \right)$

Removing the spectator ions from the ionic equation results in the net ionic equation for the given balanced chemical equation.

Therefore, the net ionic equation is

$\begin{array}{l}\\{\rm{2}}{{\rm{H}}^{\rm{ + }}}\left( {{\rm{aq}}} \right){\rm{ + 2O}}{{\rm{H}}^{\rm{ - }}}\left( {{\rm{aq}}} \right)\longrightarrow{{}}{\rm{2}}{{\rm{H}}_{\rm{2}}}{\rm{O}}\left( {\rm{l}} \right)\\\\\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\left( {{\rm{or}}} \right)\\\\{{\rm{H}}^{\rm{ + }}}\left( {{\rm{aq}}} \right){\rm{ + O}}{{\rm{H}}^{\rm{ - }}}\left( {{\rm{aq}}} \right)\longrightarrow{{}}{{\rm{H}}_{\rm{2}}}{\rm{O}}\left( {\rm{l}} \right)\\\end{array}$

Ans:

Therefore, the net ionic equation is

${{\rm{H}}^{\rm{ + }}}\left( {{\rm{aq}}} \right){\rm{ + O}}{{\rm{H}}^{\rm{ - }}}\left( {{\rm{aq}}} \right)\longrightarrow{{}}{{\rm{H}}_{\rm{2}}}{\rm{O}}\left( {\rm{l}} \right)$