# For the following aqueous reaction, complete and balance the molecular equation and write a net...

## Question:

For the following aqueous reaction, complete and balance the molecular equation and write a net ionic equation, making sure to include the physical states of the compounds: barium hydroxide + hydrocyanic acid

## Molecular, Total Ionic and Net Ionic Equations:

The molecular equation shows the complete chemical formulas of the compounds of the reactants and products involved in the reaction. The total ionic equation shows the ions of the soluble compounds in the reaction including the spectator ions. The net ionic equation includes the species that are involved in the chemical reaction. Hence, spectator ions are eliminated to obtain the net ionic equation.

The reaction between barium hydroxide and hydrocyanic acid is a double displacement reaction.

Balanced Molecular Equation: {eq}Ba(OH)_{2(aq)}+2HCN_{(aq)} \rightarrow Ba(CN)_{2(aq)}+2H_2O_{(l)} {/eq}

Barium hydroxide is a strong base and dissociates completely into its ions in solution. Hydrocyanic acid is a weak acid and is written as is in the total ionic equation. Barium cyanide is a soluble salt that also dissociates completely into its ions in solution. Water is a weak electrolyte and is also written as is in the total ionic equation.

Total Ionic Equation: {eq}Ba_{(aq)}^{2+} +2OH_{(aq)}^{-} +2HCN_{(aq)}\rightarrow Ba_{(aq)}^{2+}+2CN_{(aq)}^{-}+2H_2O_{(l)} {/eq}

The spectator ions are eliminated to obtain the net ionic equation.

Net Ionic Equation: {eq}2OH_{(aq)}^{-} +2HCN_{(aq)}\rightarrow 2CN_{(aq)}^{-}+2H_2O_{(l)} {/eq}

or {eq}OH_{(aq)}^{-} +HCN_{(aq)}\rightarrow CN_{(aq)}^{-}+H_2O_{(l)} {/eq}