Food cans are coated with tin and not with zinc because

Which process is used to determine the reactivity of a metal?

Write true or false for the following statement:
Hydrogen gas is evolved when a metal reacts with nitric acid.

Which metal is stored in kerosene?

Give reasons: $Sodium$,$potassium$,and $lithium$ are stored under oil.

During the reaction of some metals with dilute hydrochloric acid,following observations were made.
$(a)$ Silver metal does not show any change.
$(b)$ The temperature of the reaction mixture rises when aluminium $(Al)$ is added.
$(c)$ The reaction of sodium metal is found to be highly explosive.
$(d)$ Some bubbles of a gas are seen when lead $(Pb)$ is reacted with the acid.
Explain these observations giving suitable reasons.