2. REVISION C4 1 st Half!

4. How many elements are present in Na 2 CO 3 ?

5. How many atoms are present in Na 2 CO 3 ?

6. A students prepares a sample of magnesium sulfate, the expected mass is 50g but they actual produce 30g. What is the % yield for this reaction?

7. Name one artificial and one natural source of water. [2]

8. What are the 3 main chemical elements that plants need? (3)

9. Why do plants need nitrogen and what can be added to soil to increase the amount of these elements are present? (2)

10. Why is chlorine added to drinking water?

11. Why is a rinsing agent added to washing up liquid? [1]

12. Explain how a detergent works, using the following keywords; hydrophilic and hydrophobic [4]

13. Link the diagrams with the correct name; [3] diamond graphite fullerene

14. Carbon graphite conducts electricity but carbon diamond does not. Explain the reason for this. [2]