Answer
27.7 moles
Step-by-step explanation:
Data Given:
Chemical formula of Calcium carbonate = CaCO₃
no. of atoms of CaCO₃ = 8.35 x 10²⁵ atoms
moles of CaCO₃= ?
Solution
First convert number of atoms to number of molecules
As
we have 5 atoms per molecule then how many molecules will be for 8.35 x 10²⁵ atoms
So, apply unity formula
5 atoms ≅ 1 molecule of CaCO₃
8.35 x 10²⁵ atoms ≅ X molecule of CaCO₃
by doing cross multiplication
X molecule of CaCO₃ = 8.35 x 10²⁵ atoms x 1 molecule / 5 atoms
X molecule of CaCO₃ = 1.67 x 10²⁵ molecule
Formula will be used
no. of moles = no. of molecules / Avogadro's number . . . . (1)
Where
Avogadro's number = 6.022 x 10²³ molecules/mol
So,
Put values in equation 1
no. of mole = 1.67 x 10²⁵/ 6.022 x 10²³ (molecules/mol)
no. of mole = 27.7 moles
So,
moles of CaCO₃ = 27.7 moles