ACIDS & BASES AND IONIC REACTIONS

10.2 - Strong and Weak Acids

Acids are substances that produce hydronium ions, H₃O⁺, when dissolved in water.

"Strong" acids ionize completely in water. For example,

The above reaction indicates that when hydrogen chloride gas reacts with water, hydronium ions are produced in aqueous solution. Note that the arrow points to the products, indicating that virtually ALL the HCl becomes H₃O⁺ and Cl^- ions in aqueous solution. HCl is therefore a strong acid.

"Weak" acids ionize partially in water.

Acetic acid, CH₃COOH, does not completely ionize in water. Most of the acetic acid in solution remains un-ionized and a small fraction ionizes to form CH₃COO^- and H₃O⁺ ions. To represent this in a chemical equation, a double arrow is used. The longer arrow pointing toward the reactants indicates that acetic acid in solution remains un-ionized. CH₃COOH is a weak acid.

Important Acids:

In section 6.4 and section 6.5, we learned how to name binary acids and oxy acids.

Learn the names and formulae of three weak acids.

	Click on this link to view animation of strong acid and weak acid ionization
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Section 15.2
The Strengths of Acids and Bases ..p409

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