Answer:
20.6
Explanation:
I don't know how to show the work for it without pencil and paper but go from there, Good Luck!
Answer:
Mg
Explanation:
If one were comparing just the neutral atoms Mg and S, the S atom would be smaller as both elements are in the same period and sulfur is more to the right
Answer:

Explanation:
Hello there!
In this case, according to the rules for the oxidation states in chemical reactions, it is possible to realize that lone elements have 0 and since magnesium is in group 2A, it forms the cation Mg⁺² as it loses electrons and oxygen is in group 6A so it forms the anion O⁻²; therefore resulting oxidation numbers are:

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