| Test tube | Nature of solution | Change in colour of red litmus |
| A | Neutral | No change |
| B | Basic | Turns blue |
| C | Acidic | No change |
| D | Neutral | No change |

| Test tube | Nature of solution | Change in colour of red litmus |
| A | Neutral | |
| B | Basic | |
| C | Acidic | |
| D | Neutral |
| Test tube | Nature of solution | Change in colour of red litmus |
| A | Neutral | No change |
| B | Basic | Turns blue |
| C | Acidic | No change |
| D | Neutral | No change |