# Bases when dissolved in water produce ______

Bases can be defined as substances that produce hydroxide ions when dissolved in water (OH).

### Acids and bases

• An Arrhenius acid is any substance that ionizes when it dissolves in water to give the H+ or hydrogen.
• An Arrhenius base is any substance that gives the OH, or hydroxide, an ion when it dissolves in water.
• Arrhenius’s acids include HCl, HCN, and H2SO4 that ionize in water to give the H+ ion. Arrhenius bases include ionic compounds that contain the OH ion, such as NaOH, KOH, and Ca(OH)2.
• When acids are dissolved in water, an excess of hydronium is created. When bases are dissolved in water, an excess of hydroxyls is created.