Question

A 1.00 carat pure diamond has a mass of 0.2 grams. How many carbon atoms are there within this diamond?

Answer 1

`1*10^22` atoms

Explanation:

In this example you have 0.2 grams of carbon atoms. The first step is to find out how many moles this is.

The molar mass of carbon is 12.01 g/mol, you have 0.2 gram so:

`0.2 color(red)cancel(color(black)(g)) / (12.01 color(red)cancel(color(black)g)/(mol)) = 0.01665... mol`

The number of atoms can be calculated using Avogadro's constant that says that 1 mole of any element contains `6.022*10^23` atoms. So the number of atoms in this example is:

`6.022*10^23 "atoms"/color(red)cancel(color(black)(mol)) * 0.01665 color(red)cancel(color(black)(mol)) = 1 *10^22 "atoms"`