Natural Sciences and Technology Grade 6-A - Thunderbolt Kids
Natural Sciences and Technology Grade 6-A - Thunderbolt Kids Natural Sciences and Technology Grade 6-A - Thunderbolt Kids
6 Processes to purify water NEW WORDS • purify • purification • sewage waste • raw water • still 188 KEY QUESTIONS • Why is aclean water supply so important? • How can water be cleaned? • How is water cleaned by municipalities to ensure that we have clean water in our homes? 6.1 Clean water Have you ever seen asign like the one in the picture? This sign is a warning that the water is not clean and humans should not drink it as it could be dangerous to your health. If it is unsafe for consumption, it is also unsafe for swimming. A warning against drinking polluted water.
QUESTIONS 1. What does 'clean water' mean to you? 2. Can you remember what pollutants are? Write it down below. We have also learned that nature has special methods of cleaning polluted water. Water purification happens in special natural environments called wetlands. Wetlands are very ecient natural 'water treatment' facilities, but they work slowly. Humans, animals and plants need fresh water every day, and for this reason we have to clean our dirty water so that it can be reused. Cleaning dirty water is what this section is all about. Why do we need clean water? Why is it so important for humans, plants and animals to have clean water? • Our bodies contain a lot of water. In fact you are mostly water! We need water every day because we loose water everyday with the waste our bodies produce. The water we drink must be clean to prevent us from becoming sick or being poisoned. • Plants and animals need clean water too, so that they can grow and be healthy. We need healthy plants and animals in our environment because they provide an ecological balance and food. • Water is also used for fun. Water sports are a very popular recreational activity and include things like swimming, surfing and waterskiing. We want clean water in our seas and lakes so we can enjoy being in the water without becoming ill. Chapter 6. Processes to purify water DID YOU KNOW? Water is needed for humans to avoid dehydration; the amount you need each day depends on the temperature, how much activity you are involved in and other factors. 189
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6 Processes to purify water<br />
NEW WORDS<br />
• purify<br />
•<br />
purification<br />
• sewage waste<br />
• raw water<br />
• still<br />
188<br />
KEY QUESTIONS<br />
• Why is aclean water supply so important?<br />
• How can water be cleaned?<br />
• How is water cleaned by municipalities to ensure that we<br />
have clean water in our homes?<br />
6.1 Clean water<br />
Have you ever seen asign like the one in the picture? This sign is a<br />
warning that the water is not clean <strong>and</strong> humans should not drink it<br />
as it could be dangerous to your health. If it is unsafe for<br />
consumption, it is also unsafe for swimming.<br />
A warning against drinking polluted water.
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