Which of the following is a neutralization reaction?

A) [tex]$KCl (aq) + NaNO_3 (aq) \rightarrow KNO_3 (aq) + NaCl (aq)$[/tex]
B) [tex]$H_2O (l) + SO_3 (g) \rightarrow H_2SO_4 (aq)$[/tex]
C) [tex]$4 Na (s) + O_2 (g) \rightarrow 2 Na_2O (s)$[/tex]
D) [tex]$2 NO_2 (g) \rightarrow 2 NO (g) + O_2 (g)$[/tex]
E) [tex]$HNO_3 (aq) + KOH (aq) \rightarrow H_2O (l) + KNO_3 (aq)$[/tex]



Answer :

To determine which of the following reactions is a neutralization reaction, we need to understand the definition of a neutralization reaction. A neutralization reaction typically involves an acid reacting with a base to form water and a salt.

Let's examine each option:

A) [tex]\( KCl(aq) + NaNO_3(aq) \rightarrow KNO_3(aq) + NaCl(aq) \)[/tex]
- This reaction involves the exchange of ions between two soluble salts, leading to the formation of new salts [tex]\( KNO_3 \)[/tex] and [tex]\( NaCl \)[/tex]. This is a double displacement reaction, not a neutralization reaction.

B) [tex]\( H_2O(l) + SO_3(g) \rightarrow H_2SO_4(aq) \)[/tex]
- This reaction involves water reacting with sulfur trioxide to form sulfuric acid. Although this reaction forms an acid, it is not a neutralization reaction because it does not involve a base.

C) [tex]\( 4 Na(s) + O_2(g) \rightarrow 2 Na_2O(s) \)[/tex]
- This reaction is a synthesis reaction where sodium metal reacts with oxygen gas to form sodium oxide. It does not involve an acid or a base, so it cannot be a neutralization reaction.

D) [tex]\( 2 NO_2(g) \rightarrow 2 NO(g) + O_2(g) \)[/tex]
- This reaction is a decomposition reaction where nitrogen dioxide decomposes into nitrogen monoxide and oxygen gas. Again, this does not involve an acid or a base, so it is not a neutralization reaction.

E) [tex]\( HNO_3(aq) + KOH(aq) \rightarrow H_2O(l) + KNO_3(aq) \)[/tex]
- This reaction involves nitric acid [tex]\( HNO_3 \)[/tex] reacting with potassium hydroxide [tex]\( KOH \)[/tex], a base, to produce water [tex]\( H_2O \)[/tex] and potassium nitrate [tex]\( KNO_3 \)[/tex], a salt. This fits the definition of a neutralization reaction.

Among the given options, only option E satisfies the criteria for a neutralization reaction. Therefore, the neutralization reaction is:

E) [tex]\( HNO_3(aq) + KOH(aq) \rightarrow H_2O(l) + KNO_3(aq) \)[/tex]

So, the correct answer is:

E