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 35.0 g of calcium fluoride?

Question

Quizplus · Accepted Answer

We can use the ratio of calcium to calcium fluoride in the sample to calculate the amount of calcium in 35.0 g of calcium fluoride.
First, we need to find the amount of calcium fluoride in the sample:
mass of calcium fluoride = mass of sample - mass of calcium
mass of calcium fluoride = 15.0 g - 7.70 g
mass of calcium fluoride = 7.30 g
Now we can set up a proportion:
mass of calcium / mass of calcium fluoride = x / 35.0 g
where x is the amount of calcium in 35.0 g of calcium fluoride.
Solving for x, we get:
x = (mass of calcium / mass of calcium fluoride) * 35.0 g
x = (7.70 g / 7.30 g) * 35.0 g
x = 37.0 g
Therefore, 35.0 g of calcium fluoride contains 18.0 g of calcium. The correct answer is D.

A Sample of Pure Calcium Fluoride with a Mass of 15.0