Question

How do you write the balanced molecular equation for the neutralization reaction between $HCl$ and $Ba{\left( {OH} \right)_2}$ aqueous solution?

Answer 1

In an aqueous solution when an acid and base which reacts to form salt and water is called a neutralization reaction. Sodium chloride is a produced salt. When an ionic compound composed of an anion from an acid and a cation from a base produced to form a salt. The salt is an ionic compound which is neither base nor an acid.

Complete step-by-step answer: The cation which is a positive part of the base and an anion which is a negative part from an acid produce salt which is a neutral compound and these kinds of reactions is called a neutralization reaction. The neutralization reactions are of different types;
Strong Acid-Strong Base reactions: When equal amounts of a strong acid and strong base are mixed such as hydrochloric acid with sodium hydroxide, it results in the formation of a neutral solution. These products of the reaction don’t have the characteristics of either an acid or a base.
$NaOH\,(aq)\, + \,HCl(aq) \to \,NaCl(aq)\, + \,{H_2}O(l)\,$
Weak Acid or Weak Base reactions: The reaction in which at least one of the components is weak do not generally result in a neutral solution. In this one component will be strong and another component will be weak.
Example, when strong potassium hydroxide and weak nitrous acid is reacted it shows to form potassium nitrite and water.
$KOH\,(aq)\, + \,HN{O_2}(aq) \to \,KN{O_2}(aq)\, + \,{H_2}O(l)\,$
Another example, when strong hydrochloric acid is reacted with weak base ammonia it forms ammonium chloride. Ammonium chloride tends to be slightly acidic.
$HCl\,(aq)\, + \,N{H_3}(aq) \to \,N{H_4}Cl(aq)$
Barium hydroxide reacts with hydrochloric acid to form barium chloride and water. This type of reaction is Strong Acid and strong base reaction.
$\underbrace {Ba{{(OH)}_2}\,(s)\, + \,2HCl(aq)}_{244.3\,\,g\,{\text{of}}\,{\text{reactant}}}\, \to \underbrace {BaC{l_2}(aq)\, + \,2{H_2}O(l)}_{244.3\,g\,\,{\text{of}}\,{\text{product}}}\,$

Note: The Chemical reactions occurring in an aqueous solution are more accurately represented with a net ionic equation. The full ionic equation for the neutralization of hydrochloric acid by barium hydroxide is written as follows;
$B{a^{2 + \,}}(aq) + \,2O{H^ - }(aq)\, + \,2{H^ + }(aq)\, + \,\,2C{l^ - }(aq)\, \to \,B{a^{2 + \,}}(aq) + \,C{l^ - }(aq)\, + \,2{H_2}O(l)\,$
Since, in this case, both acid and base both are strong. They can fully ionize to form salt as a product. The barium and chloride ions are spectator ions in the reaction, leaving the following as the net ionic reaction.
$2O{H^ - }(aq)\, + \,2{H^ + }(aq)\,\, \to \,\,2{H_2}O(l)\,$