Here's why:
* Acids are proton donors: When a strong acid dissolves in water, it donates a proton (H+) to a water molecule, forming a hydronium ion (H3O+). This process is called ionization.
* Increased hydronium ion concentration: The formation of hydronium ions increases the concentration of H+ ions in the solution, making it acidic. The higher the concentration of H+, the stronger the acid.
Example:
Hydrochloric acid (HCl), a strong acid, dissolves in water to form hydronium ions (H3O+) and chloride ions (Cl-):
HCl(aq) + H2O(l) → H3O+(aq) + Cl-(aq)
Key point: Strong acids dissolve completely in water, meaning almost all of the acid molecules ionize to form H+ ions. This is in contrast to weak acids, which only partially ionize in water.
