A sample of pure calcium fluoride with a mass of 15.0 g contains 7.70 g of calcium.How much calcium is contained in 40.0 g of calcium fluoride?

Question

Quizplus · Accepted Answer

The ratio of calcium to calcium fluoride in the sample is:
7.70 g Ca / 15.0 g CaF2
We can use this same ratio to determine the amount of calcium in 40.0 g of CaF2:
(7.70 g Ca / 15.0 g CaF2) x 40.0 g CaF2 = 20.5 g Ca

A Sample of Pure Calcium Fluoride with a Mass of 15.0