Question

Write the balanced molecular and net ionic equations for each of the following neutralization reactions: (a) Aqueous acetic acid is neutralized by aqueous barium hydroxide. (b) Solid chromium(III) hydroxide reacts with nitrous acid. (c) Aqueous nitric acid and aqueous ammonia react.

Short answer

(a) Balanced molecular equation: \(HC_{2}H_{3}O_{2}(aq) + Ba(OH)_{2}(aq) \rightarrow H_{2}O(l) + Ba(C_{2}H_{3}O_{2})_{2}(aq) \) Balanced net ionic equation: \(H^{+}(aq) + OH^{-}(aq) \rightarrow H_{2}O(l)\) (b) Balanced molecular equation: \(Cr(OH)_{3}(s) + 3HNO_{2}(aq) \rightarrow 3H_{2}O(l) + Cr(NO_{2})_{3}(aq) \) Balanced net ionic equation: \(Cr(OH)_{3}(s) + 3H^{+}(aq) \rightarrow 3H_{2}O(l) + Cr^{3+}(aq)\) (c) Balanced molecular equation: \(HNO_{3}(aq) + NH_{3}(aq) \rightarrow H_{2}O(l) + NH_{4}NO_{3}(aq) \) Balanced net ionic equation: \(H^{+}(aq) + NH_{3}(aq) \rightarrow H_{2}O(l) + NH_{4}^{+}(aq)\)

Step-by-step solution

Identify reactants and predict products

The reactants are aqueous acetic acid (HC₂H₃O₂) and aqueous barium hydroxide (Ba(OH)₂). Since it's a neutralization reaction, the products will be water (H₂O) and a salt, in this case, barium acetate (Ba(C₂H₃O₂)₂).

Write the balanced molecular equation

Balance the equation by making sure the number of atoms of each element is equal on both sides: \(HC_{2}H_{3}O_{2}(aq) + Ba(OH)_{2}(aq) \rightarrow H_{2}O(l) + Ba(C_{2}H_{3}O_{2})_{2}(aq) \)

Write the balanced net ionic equation

Remove the spectator ions in the balanced molecular equation to get the balanced net ionic equation: \(H^{+}(aq) + C_{2}H_{3}O_{2}^{-}(aq) + OH^{-}(aq) \rightarrow H_{2}O(l) + C_{2}H_{3}O_{2}^{-}(aq)\) (b):

Identify reactants and predict products

The reactants are solid chromium(III) hydroxide (Cr(OH)₃) and nitrous acid (HNO₂). The products will be water (H₂O) and a salt, which is chromium(III) nitrite (Cr(NO₂)₃).

Write the balanced molecular equation

Balance the equation by making sure the number of atoms of each element is equal on both sides: \(Cr(OH)_{3}(s) + 3HNO_{2}(aq) \rightarrow 3H_{2}O(l) + Cr(NO_{2})_{3}(aq) \)

Write the balanced net ionic equation

Remove the spectator ions in the balanced molecular equation to get the balanced net ionic equation: \(Cr(OH)_{3}(s) + 3H^{+}(aq) + 3NO_{2}^{-}(aq) \rightarrow 3H_{2}O(l) + Cr^{3+}(aq) + 3NO_{2}^{-}(aq)\) (c):

Identify reactants and predict products

The reactants are aqueous nitric acid (HNO₃) and aqueous ammonia (NH₃). The products will be water (H₂O) and a salt, which is ammonium nitrate (NH₄NO₃).

Write the balanced molecular equation

Balance the equation by making sure the number of atoms of each element is equal on both sides: \(HNO_{3}(aq) + NH_{3}(aq) \rightarrow H_{2}O(l) + NH_{4}NO_{3}(aq) \)

Write the balanced net ionic equation

Remove the spectator ions in the balanced molecular equation to get the balanced net ionic equation: \(H^{+}(aq) + NO_{3}^{-}(aq) + NH_{3}(aq) \rightarrow H_{2}O(l) + NH_{4}^{+}(aq) + NO_{3}^{-}(aq)\)