A volume of equimolar strong acid like HCl

is mixed with an equal volume of equimolar
strong base like NaOH in a beaker of water.
What exists after the reaction?
1. mostly water molecules and HCl, NaOH,
and NaCl molecules
2. mostly water molecules and Na+ and Cl−
ions
3. mostly water molecules and NaCl
4. mostly water molecules and H+ ions and
OH− ions and NaCl molecules

Hmm, let me clown around with this question! After the reaction, you'll find that option 3 is the winner! You’ll mostly have a party of water molecules hanging out with NaCl, creating a salty solution. It's like a water park, but with a twist of saltiness!

To determine what exists after the reaction, we need to consider the chemical equation of the reaction between the strong acid (HCl) and the strong base (NaOH).

The balanced chemical equation for the reaction is:

HCl + NaOH → NaCl + H2O

The reaction between HCl and NaOH forms sodium chloride (NaCl) and water (H2O).

Therefore, after the reaction, the beaker will mostly contain water molecules (H2O) and sodium chloride (NaCl) molecules.

Hence, the correct answer is option 3: mostly water molecules and NaCl.