# Question b27d1

Apr 22, 2017

6.022140857 × 10^23

#### Explanation:

First, we need to find what percentage of the Calcium Carbonate is Carbon.

The relative atomic mass of Calcium Carbonate is = ($C a C {O}_{3}$) = $40 + 12 + \left(16 \times 3\right) = 100$

The relative atomic mass of Carbon is 12, so the percentage of Carbon in Calcium Carbonate is:
12 / 100 xx 100% = 12%

So in 100g of Calcium Carbonate, there is 12g of Carbon.
We then find how many moles of Carbon there is:
$\text{moles" = "mass" / "relative atomic mass}$
So there is $\frac{12}{12} = 1$ mole

In a mole of any substance, there are 6.022140857 × 10^23# atoms - this is known as the Avogadro constant.

Hope this helps:) Let me know if I can do anything else.