Calculation of Oxygen Atoms in 300g of CaCO3

First, we need to determine the molar mass of CaCO3, which is the sum of the atomic masses of calcium, carbon, and three oxygen atoms.

Molar Mass Calculation
- Calcium (Ca) has an atomic mass of 40.08 g/mol.
- Carbon (C) has an atomic mass of 12.01 g/mol.
- Oxygen (O) has an atomic mass of 16.00 g/mol.
- Molar mass of CaCO3 = (1 x 40.08 g/mol) + (1 x 12.01 g/mol) + (3 x 16.00 g/mol) = 100.09 g/mol.

Next, we need to determine the number of moles of CaCO3 in 300g.

Number of Moles Calculation
- Number of moles = Mass / Molar mass
- Number of moles of CaCO3 = 300g / 100.09 g/mol = 2.998 mol

Since each molecule of CaCO3 contains three oxygen atoms, we can calculate the total number of oxygen atoms present in 300g of CaCO3.

Number of Oxygen Atoms Calculation
- Number of oxygen atoms = Number of moles of CaCO3 x Number of oxygen atoms per molecule of CaCO3
- Number of oxygen atoms = 2.998 mol x 3 = 8.994

Therefore, there are approximately 9 atoms of oxygen in 300g of CaCO3.

Atomic mass of :- calcium + carbon + 3 X atomic mass of oxygen

= 40 +12+ 3 X 16
= 100 g.
so, 100 g of CaCO3 = 3 X 6.022 X 10(23) atoms of oxygen 
       1 g. of  CaCO3 = [(18.066 X 10 (23) / 100] atoms of oxygen 
     300 g. of CaCO3 = [(18.066 X 10(23) X 300) / 100] atoms of oxygen 
=54.198 X 10(23) atoms of oxygen