To determine which equation represents a neutralization reaction, we need to understand the core concept of what constitutes a neutralization reaction. A neutralization reaction occurs when an acid reacts with a base to produce a salt and water.
Let’s examine each given equation step-by-step:
1. [tex]$HCl + NaNO_3 \rightarrow HNO_3 + NaCl$[/tex]
- Hydrochloric acid ([tex]$HCl$[/tex]) reacts with sodium nitrate ([tex]$NaNO_3$[/tex]).
- Products: Nitric acid ([tex]$HNO_3$[/tex]) and sodium chloride ([tex]$NaCl$[/tex]).
- This is not a typical acid-base neutralization reaction, as it does not produce water.
2. [tex]$2 KBr + MgSO_4 \rightarrow K_2SO_4 + MgBr_2$[/tex]
- Potassium bromide ([tex]$KBr$[/tex]) reacts with magnesium sulfate ([tex]$MgSO_4$[/tex]).
- Products: Potassium sulfate ([tex]$K_2SO_4$[/tex]) and magnesium bromide ([tex]$MgBr_2$[/tex]).
- This is a double displacement reaction, not a neutralization reaction.
3. [tex]$2 H_2O + 2 K \rightarrow 2 KOH + H_2$[/tex]
- Water ([tex]$H_2O$[/tex]) reacts with potassium ([tex]$K$[/tex]).
- Products: Potassium hydroxide ([tex]$KOH$[/tex]) and hydrogen gas ([tex]$H_2$[/tex]).
- This is an alkali metal reaction with water, not a neutralization reaction.
4. [tex]$RbOH + H_2SO_4 \rightarrow Rb_2SO_4 + H_2O$[/tex]
- Rubidium hydroxide ([tex]$RbOH$[/tex]) reacts with sulfuric acid ([tex]$H_2SO_4$[/tex]).
- Products: Rubidium sulfate ([tex]$Rb_2SO_4$[/tex]) and water ([tex]$H_2O$[/tex]).
- This fits the definition of a neutralization reaction, where a base (RbOH) reacts with an acid (H_2SO_4) to produce a salt (Rb_2SO_4) and water (H_2O).
Therefore, the correct equation that represents a neutralization reaction is:
[tex]\[ \boxed{RbOH + H_2SO_4 \rightarrow Rb_2SO_4 + H_2O} \][/tex]
