The first compound, HCl is called hydrogen chloride and in solution it completely dissociates into its respective ions H+ and Cl- and is called hydrochloric acid. So it forms two ions.
HCl ---> H+ + Cl-
The second compound, CCl4, is called carbon tetrachloride. It is not an ionic compound and in water does not dissociate into any ions.
The third compound, Ca(NO3)2, is called calcium nitrate. It completely dissociates in water into three different ions, the calcium ion (Ca++) and two nitrate ions (2 NO3-).
The fourth compound, Li3N, is called lithium nitride. You might think that in water it would dissociate into two ions (Li+ and Li2N-), but in reality Li3N is an extremely reactive compound that reacts violently with water to produce ammonia via the equation below:
Li3N + 3H2O --> 3LiOH + NH3
The 3 LiOH produced would dissociate in water to produce 3 Li+ and 3 OH- for a total of 6 ions.