3.53. Properties of Bases http://www.ck12.org
3.53 Properties of Bases
- Define base.
- Identify properties of bases.
- Describe how to detect and measure the strength of bases.
- List some uses of bases.
These blocks of baking chocolate may make your mouth water, but if you were to taste them, you would be in for
an unpleasant surprise. The blocks are unsweetened chocolate. Without any added sugar, chocolate tastes bitter.
Chocolate tastes bitter because it’s a base.
What Are Bases?
Bases are ionic compounds that produce negative hydroxide ions (OH−) when dissolved in water. An ionic com-
pound contains positive metal ions and negative nonmetal ions held together by ionic bonds. (Ions are atoms that
have become charged particles because they have either lost or gained electrons.) An example of a base is sodium
hydroxide (NaOH). When it dissolves in water, it produces negative hydroxide ions and positive sodium ions (Na+).
This can be represented by the equation:
NaOH
H 2 O
→OH−+ Na+Properties of Bases
All bases share certain properties, including a bitter taste. (Warning:Never taste an unknown substance to see
whether it is a base!) Bases also feel slippery. Think about how slippery soap feels. That’s because it’s a base.
In addition, bases conduct electricity when dissolved in water because they consist of charged particles in solution.
(Electric current is a flow of charged particles.)