Give reason for the following.

Chlorine displaces bromine from potassium bromide. 

An atom of an element $\mathrm{X}$ has $2$ electrons in its $\mathrm{N}$ shell.

(i) State its electronic configuration.

(ii) Is it a metal or non-metal?

(iii) State the number of protons in $\mathrm{X}$.

(iv) Write the formula of its chloride.

(v) Where is this element placed in the periodic table?

(i) Copper sulphate crystals are heated strongly in a hard glass test tube. Write three observations noticed. 

(ii) Write the main equation for the above.