Is baking soda and water a solution or suspension?

When baking soda (sodium bicarbonate) is mixed with water, it completely dissolves in the water and forms a homogeneous mixture where the solute particles (baking soda) are evenly distributed throughout the solvent (water). This mixture is known as a solution.

In a solution, the solute particles are small enough to pass through a semipermeable membrane and remain dispersed in the solvent. This is not the case for a suspension, where the particles are larger and can be separated from the liquid by filtration.