Question 3: Empirical and Molecular Formula (1 point) a. What is the difference between the empirical formula and the molecular formula? (.5 point)

b. How does one determine the molecular formula from the empirical formula? (.5 point)

Question 4: Percent Composition (3.5 points)

a. How is the percent composition by mass determined? (.5 point)

b. Determine the percent composition of each element in MgCl2. (1 point)

i. Magnesium (Mg): (.5 point)

ii. Chlorine (Cl): (.5 point)

c. Calculate the empirical formula from the given percent compositions.
82% nitrogen (N), 18% hydrogen (H) (2 points)