| A | B |
|---|
| pH scale | ranges from 0-14 and is used to measure how acidic or basic a substance is |
| acid | has more free hydrogen ions; ranges from 0-6 on the pH scale |
| base | has more free hydroxide ions; ranges from 8-14 on the pH scale |
| ion | atom that has a positive or negative charge from gaining or losing electrons |
| neutral | neither positive nor negative; 7 on the pH scale |
| acid rain (definition) | falling to earth of rain, snow or dry particles containing certain pollutants; more acidic than normal rainwater |
| 5.6 | pH scale reading for normal rainwater which is slightly acidic |
| 5.0 or less | pH scale reading for acid rain |
