First, we need to find what percentage of the Calcium Carbonate is Carbon.
The relative atomic mass of Calcium Carbonate is = (
The relative atomic mass of Carbon is 12, so the percentage of Carbon in Calcium Carbonate is:
So in 100g of Calcium Carbonate, there is 12g of Carbon.
We then find how many moles of Carbon there is:
So there is
In a mole of any substance, there are
Hope this helps:) Let me know if I can do anything else.