Name two metals which are found in nature in the free state.

Metallic oxides of zinc,magnesium,and copper were heated with the following metals. In which cases will you find displacement reactions taking place?

Differentiate between metal and non-metal on the basis of their chemical properties.

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

Samples of four metals $A$,$B$,$C$ and $D$ were taken and added to the following solutions one by one. The results obtained have been tabulated as follows.

Metal	Iron $(II)$ sulphate	Copper $(II)$ sulphate	Zinc sulphate	Silver nitrate
$A$	No reaction	Displacement	No reaction	Displacement
$B$	Displacement	Displacement	No reaction	Displacement
$C$	No reaction	No reaction	No reaction	Displacement
$D$	No reaction	No reaction	No reaction	No reaction

Use the table above to answer the following questions about metals $A$,$B$,$C$ and $D$:
$(i)$ Which is the most reactive metal?
$(ii)$ What would you observe if $B$ is added to a solution of Copper $(II)$ sulphate?
$(iii)$ Arrange the metals $A$,$B$,$C$ and $D$ in the order of decreasing reactivity.

Why is sodium kept immersed in kerosene oil?