Answer:
Magnesium and Sulfur
Explanation:
If you take a look at the periodic table, you would see that Fluorine and Sulfur are positioned in the P - block, so that it should be a non - metal. Respectively Magnesium and Sodium belong to the S - block, and are hence metals.
There are two approaches to solving this problem;
1. Take a look at the position of each elements and see how many steps they are to the nearest noble gas configuration. If they need have to go back steps they would tend to lose electrons, and form a cation.
2. Check the position of each element and note if it is a metal or nonmetal. Metals tend to lose electrons and form cations
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I have already started on the second approach. Thus, it should be that Magnesium and Sulfur meet the requirements listed ( lose electrons, form cations )
