When we are in the wild, we find that water is important for us to live. There are many ways to get some clean water. For example, if there is fire and enough water, the best way is to boil the water. But in many cases, there doesn't seem to be any safe water available.
Can you think of a way of cleaning dirty water by using the sun? In this activity, you will make a "solar still (太阳能蒸馏器)". Let's get started to make pure water (纯净水)!
Things to prepare:☆a wide plastic basin (塑料盆) ☆a large piece of plastic paper ☆a smaller glass for collecting the clean water ☆a thin string (绳子) ☆salt and stone Steps: 1. Mix salt with water. Put salty water in your basin. 2. Put your collecting glass in the middle of your basin. 3. Cover the basin with the plastic paper. Use a string to seal ofthe edges (封住边缘). 4. Place a stone in the middle of the plastic paper just above your collecting glass. 5. Carefully move the solar still into the sun so that the sun can heat (加热) the salty water and turn it into vapor (水蒸汽). … |
