Why is sodium kept immersed in kerosene oil?

You are given a hammer,a battery,a bulb,wires,and a switch.
$(a)$ How could you use them to distinguish between samples of metals and non-metals?
$(b)$ Assess the usefulness of these tests in distinguishing between metals and non-metals.

Give reasons: Aluminium is a highly reactive metal,yet it is used to make utensils for cooking.

Give an example of a metal which:
$(i)$ is a liquid at room temperature.
$(ii)$ can be easily cut with a knife.
$(iii)$ is the best conductor of heat.
$(iv)$ is a poor conductor of heat.

State two ways to prevent the rusting of iron.

What would you observe when zinc is added to a solution of iron $(II)$ sulphate? Write the chemical reaction that takes place.