The diagram below shows the electrical method of magnetizing a nail.

Study the diagram and use it to answer the questions that follow.

1. Give the names of the parts of the circuit labelled I, II and III

2. List two substances that can be made into a magnet.

3. State two other methods of making magnets.

4. Name one material that is used in making an electrical wire

5. Give two properties of the material you named in (iv) which makes it useful as a wire. [10 marks]

The diagram below shows the set-up for the preparation of carbon dioxide in the laboratory.

1. Name the parts of the set-up labelled I and II

2. Give the name of the method of gas collection shown in the diagram.

3. Give one property of gases collected over water.

4. What will happen if component I does not dip into the contents of the flask?

5. List two compounds that form the content of the flask.

6. Write down the systematic name of carbon dioxide. [10 marks]

In an experiment, yam pap is put into two test tubes A and B containing iodine solution. The test tubes are warmed slightly to a temperature of 37°C and saliva is put into test tube B

1. State the colour of the content of test tube A.

2. State the colour changes of the contents in test tube B after about 3 minutes.

3. Fehling’s solution is added to the contents of test tube B after the 3 minutes and it turns brick red. What food substance is present?

4. (iv) Give two functions of saliva in eating.

5. Why was it necessary to warm the contents of the test tubes to about 37°C?

6. Give two aims of the experiment. [10 marks]