Solve this :
(a) (i) In covalent compounds, the bond is formed due to ............. [sharing/transfer] of electrons. 
(ii) Electrovalent compounds have a ................ [low/high] boiling point. 
(iii) A molecule of .............. contains a triple bond.  [hydrogen, ammonia, nitrogen]. 

(b) By drawing an electron dot diagram, show the lone pair effect leading to the formation of — ammonium ion from ammonia gas and hydrogen ion. 

(c) Give reasons — Hydrogen chloride can be termed as a polar covalent compound.