2. REVISION C4 1 st Half! (H)

4. An acid can be neutralised by adding a ______ or an ______ to it. An _______ is a soluble _______. An alkali can be neutralised by adding an ______ to it. (5) ACID ALKALI BASE ALKALI BASE

5. How many elements and atoms are in this compound? (explain your answer) CaCO 3

6. What do we call solutions with a pH of less than 7, exactly 7, and more than 7

7. Complete the neutralisation equation Base + ______________ + salt

8. A process has a predicted yield of 50 kg but only 12.5 kg is produced calculate the percentage yield. (explain your answer) Percentage yield =actual yield x 100 Predicted yield

9. Calculate the formula mass of ammonia N: 14 H:1 3 NH

10. State two reasons fertilisers are put onto crops

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

12. What must fertilisers do before they can be absorbed by plants (2)

13. What are the two elements that ammonia is made from

14. Which acid and base are needed to make the following fertilisers; ammonium sulphate and ammonium nitrate. (3)

15. List three factors that affect the cost of making a substance

16. Match these squares up The higher the pressure The higher the temperature Using a catalyst Increases the plant cost Increases the energy cost Reduces the cost by increasing the reaction rate

17. What does this symbol mean?