Answer:
I think its might be 1 because the ionic numbers for CA is +2 and for P its +3
Heat radiates from the fire and cooks the marshmallow because heat transfer.
One is through sublimation, where the mixture is heated and iodine gets converted into gaseous form, leaving behind the iron fillings.
The other is to get a magnet near the mixture and all the iron fillings get attracted to it while iodine will be left over
Answer=1
Potassium Sulfide= K2S (two metals, one non metal)
Sodium Oxide=Na2O (two metals. one nonmetal)
Sodium Chloride=NaCl (one metal, one nonmetal)
Magnesium Oxide=MgO (one metal, one nonmetal)
Magnesium Chloride=MgCl2 (one metal, two nonmetals)