Topic C10- Using Resources Flashcards
What is potable water?
Water that has been treated or naturally safe for humans to drink
How can filtration and sterilisation be used to treat water?
Filtration- a wire mesh screens out large twigs. Then gravel and sand beds filter out any other solid bits
Sterilisation- bacteria and microbes are killed by bubbling chlorine gas through it or by using ozone or ultraviolet light
What are the four steps of distillation to purify water?
1) First, neutralise the water by adding some acid or some alkali until the pH is 7
2) Heat up the water so it evaporates and enters the condenser as steam. The condenser will cause the steam to condense due to the cold water around it.
3) Retest the pH using a pH meter to check it’s neutral.
4) Once the water’s been distilled you can check if there are any crystals in the round bottom flask, to tell whether there were salts
