The reaction of sodium hydroxide (NaOH) with water (H₂O) is an exothermic reaction, but it doesn't actually form a new chemical compound. Instead, it's a dissolution process where NaOH dissolves in water, releasing heat and forming ions.

Here's the balanced equation:

NaOH(s) → Na⁺(aq) + OH⁻(aq) + Heat

Explanation:

* NaOH(s): Solid sodium hydroxide

* Na⁺(aq): Sodium ion dissolved in water

* OH⁻(aq): Hydroxide ion dissolved in water

* Heat: Energy released as heat

Important Note: While there is no new compound formed, the reaction is exothermic because the dissolving process releases energy (heat) into the surroundings. This is due to the strong attraction between water molecules and the ions of NaOH, causing the ionic bonds within NaOH to break and release energy.