Select all cases in which the units comprising the solid are best classified as ions?

Question

Select all cases in which the units comprising the solid are best classified as ions?
P4
Mg(ClO3)2  	  
Ge
Pb(NO3)2
Ag
C2H4O2

DrBob222 · Answer

You don't expect the elements P4, Ge, and Ag to be anything but covalent bonds. C2H4O2 might be anything but it could be acetic acid which is largely a covalent compound. The other two are salts that have a crystal structure largely made up of the ions.