Question

A compound contains 14.5 g of magnesium and 3.5 g of oxygen. What is the mass percent of oxygen in the compound

Answer 1

♥ Gather information we know:
Total Mass: $14.5+3.5$
Solve:
$=18g$
Gather more information and solve:
Percent of Oxygen: $\frac{3.5}{18}$  $* 100$


Final answer: 19.44% 

Answer 2

Answer:

For Edmentum/Plato users, the correct answer is B. 19.44%