In a neutralization reaction, an acid reacts with a base to form water (H₂O) and a salt. The base given in the reaction is potassium hydroxide (KOH), and the salt produced is potassium bromide (KBr). We need to determine the missing component on the left side of the equation.
The general form of a neutralization reaction is:
[tex]\[ \text{Acid} + \text{Base} \rightarrow \text{Water} + \text{Salt} \][/tex]
Here, the base is KOH, and the salt is KBr. To determine the missing acid, we need to identify an acid that would react with KOH to form KBr.
Given that:
Base: [tex]\( KOH \)[/tex]
Salt: [tex]\( KBr \)[/tex]
To get KBr as the salt, the acid must provide the bromide ion (Br⁻). When KOH (a strong base) reacts with an acid that contains bromide (Br⁻), it will neutralize to form water and the salt KBr. The simplest acid that contains the bromide ion is hydrobromic acid (HBr).
[tex]\[ \text{HBr} + \text{KOH} \rightarrow \text{H}_2\text{O} + \text{KBr} \][/tex]
Thus, the complete and balanced reaction would be:
[tex]\[ \text{HBr} + \text{KOH} \rightarrow \text{H}_2\text{O} + \text{KBr} \][/tex]
Therefore, the missing component in the reaction is [tex]\( \text{HBr} \)[/tex].
So the correct option is:
B. [tex]\( \text{HBr} \)[/tex]
