1. Module 5 Intro

1.22. Page 7

Lesson 3

Module 5—Acids and Bases

Lesson Summary

 

The following critical questions were discussed in this lesson:

  • How are the empirical properties of weak acids and bases different from those of strong acids and bases?

  • What are polyprotic acids and bases?

Acids and bases have varying properties depending on the degree of ionization or dissociation. A strong acid, such as HCl(aq), and a weak acid, such as CH3COOH(aq), can have different pH values even though the concentration of each acid is the same. Other empirical properties—such as conductivity, pH, and rate of reaction—are more pronounced when comparing solutions containing strong acids than for weak acid solutions with identical solute concentration.


Polyprotic acids and bases may undergo successive reactions with water to produce hydronium ions or hydroxide ions. In the majority of cases, only the first reaction of a polyprotic substance contributes significantly to the overall pH of a solution.

 

Lesson Glossary

 

monoprotic acid: an acid that possesses only one ionizable proton and can react only once with water to produce hydronium ions

 

monoprotic base: a base that can react only once with water to produce hydroxide ions

 

polyprotic acid: an acid with more than one acidic hydrogen available to react with water to produce hydronium ions

 

polyprotic base: a base that can react more than once with water to form hydroxide ions

 

strong acid: a substance that forms a solution with strong acidic properties

 

Strong acids react completely (>99%) with water to form hydronium ions.

 

strong base: a substance that forms a solution with strong basic properties

 

Strong bases are ionic hydroxides that dissociate completely (>99%) to release hydroxide ions.

 

weak acid: a substance that forms a solution with weak acidic properties

 

Weak acids react incompletely with water (<50%) to form relatively few hydronium ions.

 

weak base: a substance that forms a solution with weak basic properties

 

Weak bases react partially with water (<50%) to produce relatively few hydroxide ions.