Bonding is ionic for sure
Mg has lost 2e,s to become Mg2+
and there are 2 Cl-
the strong attraction between the Mg2+ and 2Cl- form the ionic bonding
The answer would be D because from my research it's the only one that didn't have a catalyst
Answer: 2.3
Explanation: 3.5 (O) - 1.2 (Mg) = 2.3