Detecting Acids and Bases
Red cabbage water is an indicator
of pH. Although it can't be used to determine exact pH, it can
distinguish between acid (pH of 0 to 6), neutral (pH near 7),
and base (pH of 8 to 14).
acid neutral base
0 1 2 3 4
5 6 7 8 9
10 11 12 13 14
In this activity:
- If the indicator turns the solution red or pink, the solution
is an acid.
- A purple solution indicates that it is neutral, neither an
acid nor a base.
- If the indicator turns the solution blue or green, the solution
is a base.