Chem homework, help please?

When Magnesium combines with Chlorine, what will be the ionic bond?

ClMg2

MgCl2

Mg2Cl2

MgCl

When Lithium combines with Nitrogen, what will be the ionic bond?

LiN

LiN3

Li3N

Li3N3

When Aluminum combines with Oxygen, what will be the ionic bond?

AlO

Al3O

Al2O3

Al2O2

Strontium reacts with a certain element to form compound with the general formula SrX. What would be the most likely formula for the compound formed between Potassium and Element X?

K2X

KX2

K2X3

K2X2

For the first Q: MgCl2 because Mg is in group two and therefore needs 2 extra electrons to fill its outer shell. Likewise Cl is in group 7 and only needs one extra electron so there have to be two chlorine atoms for one magnesium atom to ensure that both the Mg and the two Cl atoms have full outer shells.

Q2: Li3N let’s see if you were listening above ;)

Q3: Al2O3

Q4: K2X

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