1. Definitions Indicators and Measurements
Acids and Bases
Definitions
Indicators and
Measurements

2. Definitions
pH: measure of the acidity or alkalinity of a substance, non-characteristic property
Acid: a substance with a pH value less than 7, ex- lemon juice
Base: a substance with a pH value over 7, ex- bleach
Neutral: a substance with a pH of 7, only distilled(pure) water
Indicator: a substance that changes color in the presence of an acid or a base, ex- Litmus paper and Universal pH paper

3. Litmus Paper BLUE Litmus paper  red = acid
RED Litmus paper  blue = base
BLUE and RED Litmus paper  remain the same colour = neutral

4. Universal pH Paper More accurate than Litmus paper
Indicates the substance’s level of pH, between 1(more acid) and 14 (more basic)