Question

Which of the following is an acid-base neutralization reaction?
(A) \[A{g^ + }\;\left( {aq.} \right) + C{l^ - } \to AgCl(aq)\]
(B) \[{C_5}{H_{12}}(s) + 8{O_2}(g) \to 5C{O_2}(g) + 6{H_2}O(l)\]
(C) \[N{H_3}(s) + {H_2}O(s) \rightleftharpoons N{H_4}^ + (s) + O{H^ - }(s)\]
(D) \[H{C_2}{H_3}{O_2}(l) + O{H^ - }(aq) \to {H_2}O(O) + {C_2}{H_3}{O_2}(aq)\]
(E) $CaC{O_3}(s) \to CaO(s) + C{O_2}(g)$

Answer 1

Hint: When acid and base react with each other, they form a neutralized salt and the reaction is called neutralization reaction.
\[Acid{\text{ }} + {\text{ }}Base \to \;Salt{\text{ }} + {\text{ }}Water\]
Thus, the reaction with no excess of hydrogen or hydroxide ions present in solution is called an acid-base neutralization reaction.

Complete step by step answer:
As we know, when an acid and base of equal strength, reacts with each other, they nullify the effect of each other. This reaction between acid and base is called neutralization reaction. The acid and base of some strength reacts to form a neutralised salt and the water.
i.e.
\[Acid{\text{ }} + {\text{ }}Base \to \;Salt{\text{ }} + {\text{ }}Water\]
Acids are commonly those which dissociates in water to give \[{H^ + }\] ions and bases are those which dissociates in water to give \[O{H^ - }\]ions.
Now according to given questions, let us try to find the correct option. In option (A), \[A{g^ + }\] (aq.) and \[C{l^ - }\] (aq.) combine together to give \[AgCl\left( {aq.} \right)\]. Since the product is formed by the combination of the reactants. So it is an example of an additional reaction. In option(B) a hydrocarbon \[\left[ {Pentane} \right]{\text{ }}{C_5}{H_{12}}\] is treated with oxygen to give carbon dioxide (\[C{O_2}\]) and water (\[{H_2}O\]) as the product. Since hydrocarbon is treated with the oxygen means that the pentane is burnt in the presence of oxygen. So, in option (B), combustion of \[{C_5}{H_{12}}\] takes place. In option (\[C\]), ammonia (\[N{H_3}\]) is added to water which accepts protons from water molecule to give polar solution of \[N{H_4}^ + (S)\] and \[O{H^ - }\left( S \right)\;\;\]. So it is not the neutralization reaction. In option ( E ), one reactant [\[CaC{o_3}\]] decomposes to give the two products [\[CaO{\text{ }} + {\text{ }}C{O_2}\] ]. Hence, option ( E ) is a type of decomposition reaction. Now in option (D), \[H{C_2}{H_3}{O_2}\] is acetic acid [\[C{H_3}COOH\]]. Being an acid it releases \[{H^ + }\]which combines with \[O{H^ - }\]from the base to give the neutralization reaction.
i.e.
\[H{C_2}{H_3}{O_2}(l) + O{H^ - }(aq) \to {H_2}O(l) + {C_2}{H_3}{O_2}^ - (aq)\]
\[Acetic{\text{ }}Acid\;\;\;\;\;\;\]\[From{\text{ }}Base\;\;\;\;\;\;\;\;\;\;\;\;\;\] \[\;Water\;\;\;\;\] \[Salt\]

So, the correct answer is Option D.

Note: It is to be noted that most ionic salts exist as free ions in their aqueous solutions, thus presence of alkali hydroxides is equivalent to the presence of hydroxide ions. \[O{H^ - }\]ion can be taken from any base such as \[NaOH\]and \[KOH\]. So \[O{H^ - }\]also signifies the presence of base in the solution.