Here's why:

* Ionic compound: Sodium bicarbonate is an ionic compound, meaning it's made up of positively charged sodium ions (Na+) and negatively charged bicarbonate ions (HCO3-).

* Polar solvent: Water is a polar solvent, meaning it has a positive and negative end due to the uneven sharing of electrons.

* Attraction: The positive ends of water molecules are attracted to the negative bicarbonate ions, and the negative ends of water molecules are attracted to the positive sodium ions.

* Dissociation: This attraction breaks apart the ionic bonds in sodium bicarbonate, causing it to dissolve and form a solution of sodium and bicarbonate ions in water.

However, it's important to note that the solubility of sodium bicarbonate is limited. A saturated solution at room temperature contains about 9.6 grams of sodium bicarbonate per 100 mL of water.