Which method/process is used to obtain aluminium from pure alumina?

Which metal reacts with cold water violently?

$(a)$ Why does calcium start floating when added to water?
$(b)$ Most metals do not release hydrogen gas when reacting with nitric acid. Why?
$(c)$ Write the chemical equation for the reaction of iron with steam. Name the compound of iron obtained.

Give a reason to explain:
$(i)$ Why do aluminium sheets not corrode easily?
$(ii)$ Why is a copper vessel covered with a green coating in the rainy season?

Write the electron dot structures of magnesium and chlorine and show the formation of magnesium chloride by the transfer of electrons.

Give reasons for the following:
$(a)$ School bells are made of metals.
$(b)$ Electrical wires are made of copper.