- Physical Appearance Test: Check if the liquid is clear and transparent, without any suspended particles or cloudiness.
- Odor Test: Pure water should have no distinct odor. If it smells like anything other than water (such as chemicals or contaminants), it may not be pure.
- Taste Test: Pure water should have a clean, neutral taste. If it tastes salty, metallic, or has any other flavor, it may not be pure.
- Boiling Point Test: Boil the liquid and observe its boiling point. Pure water boils at 100°C (212°F) at standard atmospheric pressure. Any deviation from this temperature may indicate impurities.
- Freezing Point Test: Check if the liquid freezes at 0°C (32°F). Pure water freezes at this temperature. Any deviation may suggest impurities.
- Conductivity Test: Pure water is a poor conductor of electricity. You can use a conductivity meter to check if the liquid conducts electricity. If it does, it likely contains dissolved ions or impurities.
- Chemical Test: Perform chemical tests such as adding a few drops of universal indicator or pH paper to check if the liquid has a pH of around 7, indicating neutrality.
