2. Separating mixtures and solutions: Evaporation Mixtures and Solutions

3. All water, even rainwater, contains dissolved chemicals called salts. Not all water tastes salty, however.

4. The world’s rivers carry about 4 billion tonnes of dissolved salts to the oceans every year. Salts become concentrated in the oceans because the heat of the Sun causes evaporation of water from the surface, leaving the salts behind.

5. Percentage of salt in some bodies of water Arabian Sea 3.7% Atlantic and Pacific Oceans 3.2–3.7% Baltic Sea 1% Dead Sea 27% Great Salt Lake 5–27% Red Sea 4.1%

6. Most of Earth’s water is too salty to drink or to use for irrigation. How can the dissolved salt be removed, so the water will meet people’s needs?

7. It is relatively easy to recover the solute from seawater—leave the seawater in the sunlight, and let the water evaporate. Eventually you will be left with solid salt.

8. However, recovering the solvent from the solution is more complicated...

9. Distillation: separating the parts of a solution glass tubing flask rubber stopper blue liquid hot plate plastic tubing beaker

10. Evaporation is used in other industries as well…

11. Evaporation that is too slow or too fast will affect the colour, flavour, and texture of the syrup.Evaporation that is too slow or too fast Evaporation in the Maple Sugar Industry

12. Bees make honey from a solution of water and sugar called nectar. Nectar is collected from flowers and then stored in the open cells of the beehive. Bees fan their wings in front of the cells to evaporate the excess water in the nectar. As the water content drops (from 70% to 20%) honey is produced. Evaporation in the Honey Industry

13. Western Canada uses domestically grown sugar beets as the raw ingredient for its sugar. Evaporation in the Sugar Industry

14. Eastern Canada produces most of its sugar using imported sugar cane as the raw ingredient.

15. 4: spinning3: evaporation2: crushing & washing Making sugar from sugar cane 1: delivery 5: After spinning, the liquid (molasses) is separated from the brown sugar crystals. These can be further processed to produce white sugar.