When you mix hydrogen chloride (HCl, a strong acid) and sodium hydroxide (NaOH, a strong base), you get a neutralization reaction. This means the acid and base react to form salt and water.

Here's the chemical equation:

HCl (aq) + NaOH (aq) → NaCl (aq) + H₂O (l)

Here's what happens:

* Hydrogen ions (H+) from the acid react with hydroxide ions (OH-) from the base. This forms water (H₂O).

* The remaining ions, sodium (Na+) and chloride (Cl-) combine to form sodium chloride (NaCl), which is table salt.

* The reaction releases heat, making the solution warmer.

In summary: Mixing hydrogen chloride and sodium hydroxide results in a neutralization reaction, producing salt (sodium chloride) and water. The reaction is exothermic, meaning it releases heat.