Answer:
The empirical formula of the compound is
.
Explanation:
Mass of magnesium in compound = 0.273 g
Mass of nitrogen in the compound = 0.105 g
Moles of magnesium =
Moles of nitrogen = 
Form empirical formula divides the lowest value of moles of an element present with all the moles of elements present.
Magnesium 
Nitrogen 
The empirical formula of a compound:

The empirical formula of the compound is
.
Assuming there is excess acid, the equation for the reaction is Zn + 2HCl -> ZnCl2 + H2.
Mols of zinc = 20/65 (mass/relative atomic mass)
Ratio of Zn : ZnCl2 = 1 : 1
Hence mols of Zinc = mols of Zinc chloride
Mass of ZnCl2 = (20/65)(65+71)
= 41.8g
Answer
The negative ion is larger than the original atom.
Explanation:
This means that with fewer electrons but the same number of positive protons, the size of the ionic radius will decrease.
I hope this helped!