1. 4.2 What’s in Clean Water Pages 275-279

2. Bottled Water Toronto tap water is safer to drink than bottled water. Tap water has more strict regulations placed on water quality than bottled water does.

3. Sources Bottled water comes from: -underground springs and wells -municipal water supply Water must be Boiled and Condensed.

4. Flavour Water percolates through soil picking up Fe 3+, Fe 2+, Ca 2+ and Mg 2+ which taste good. Too much iron? Water tastes rusty. Too much sulfur ? Water smells bad.

5. Avoid these! Heavy metals harm organs and central nervous system. Examples: lead, mercury, arsenic, cadmium

6. Hard Water Ca 2+ and Mg 2+ as well as Fe 3+, Fe 2+, Mn 2+. >50ppm soft water 400-600ppmhard water Scaling on pots and kettles Soap scum

7. Water Softeners Displace calcium ions using sodium ions

8. How it works When hard tap water passes through the ion exchanger the calcium ions from the tap water replace the sodium ions in the ion exchanger. The softened water, containing sodium ions in place of calcium ions, can be collected for household use.

9. Dissolved oxygen Cold water holds more oxygen than warm water.

10. Aeration Oxygen is bubbled into white water (rapids, water falls, white capped-waves) Also… Oxygen dissolves directly into water from the air above it. Plants photosynthesize adding oxygen to the water directly.