What is the complete ionic equation for [tex]NaOH (aq) + HCl (aq) \rightarrow H_2O (l) + NaCl (aq)[/tex]?

A. [tex]OH^{-} + H^{+} \rightarrow H_2O[/tex]
B. [tex]Na^{+} + OH^{-} + H^{+} + Cl^{-} \rightarrow H_2O + Na^{+} + Cl^{-}[/tex]
C. [tex]Na^{+} + Cl^{-} \rightarrow NaCl[/tex]
D. [tex]Na^{+} + OH^{-} + H^{+} + Cl^{-} \rightarrow H^{+} + OH^{-} + Na^{+} + Cl^{-}[/tex]



Answer :

To determine the complete ionic equation for the reaction \( NaOH (aq) + HCl (aq) \rightarrow H_2O (l) + NaCl (aq) \), we should first write the complete balanced molecular equation and then break all the soluble ionic compounds into their respective ions.

Step-by-step solution:

1. Write the balanced molecular equation:
[tex]\[ NaOH (aq) + HCl (aq) \rightarrow H_2O (l) + NaCl (aq) \][/tex]

2. Identify the strong electrolytes that dissociate completely in water:
- \( NaOH \) (Sodium hydroxide) dissociates into \( Na^+ \) and \( OH^- \).
- \( HCl \) (Hydrochloric acid) dissociates into \( H^+ \) and \( Cl^- \).
- \( NaCl \) (Sodium chloride) dissociates into \( Na^+ \) and \( Cl^- \).

3. Write the complete ionic equation:
[tex]\[ Na^+ (aq) + OH^- (aq) + H^+ (aq) + Cl^- (aq) \rightarrow H_2O (l) + Na^+ (aq) + Cl^- (aq) \][/tex]

4. Identify and remove the spectator ions:
Spectator ions are ions that appear on both sides of the equation without undergoing any change. Here, \( Na^+ \) and \( Cl^- \) are spectator ions.

5. Write the net ionic equation:
Remove the spectator ions (\( Na^+ \) and \( Cl^- \)):
[tex]\[ OH^- (aq) + H^+ (aq) \rightarrow H_2O (l) \][/tex]

So, based on the given options, the complete ionic equation matches with:

B. [tex]\( Na^+ + OH^+ + H^+ + Cl^- \rightarrow H_2O + Na^+ + Cl^- \)[/tex]