Answer:
Step-by-step explanation:
1 mol of N2 = 2 * 14 grams = 28 grams
3.400 moles of N2 = x
x = 3.400 * 28
x = 95.20 grams of Nitrogen
1 mol of magnesium = 24 grams
2.5 moles of magnesium = x Cross multiply
x = 24*2.5
x = 60
The Nitrogen has more mass.
Note: this is a guide on how to do the question. Chemistry has all sorts of periodic tables. Just us the mass numbers in your periodic table.