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.
$(a) $ With the hammer, we can beat the sample and if it can be beaten into thin sheets (that is, it is malleable), then it is a metal otherwise a non-metal. Similarly, we can use the battery, bulb, wires, and a switch to set up a circuit with the sample. If the sample conducts electricity, then it is a metal otherwise a non-metal.
$(b)$ The above tests are useful in distinguishing between metals and non-metals as these are based on the physical properties. No chemical reactions are involved in these tests.
What would you observe when zinc is added to a solution of iron $(II) $ sulphate ? Write the chemical reaction that takes place.
Which gas is produced when dilute hydrochloric acid is added to a reactive metal? Write the chemical reaction when iron reacts with dilute $H_2SO_4$.
What type of oxides are formed when non-metals combine with oxygen?
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 conduct of heat.
Give reasons why copper is used to make hot water tanks and not steel (an alloy of iron).