Answer :
Calcium carbonate is CaCO3.
So there is calcium, symbol is Ca and an atomic number of 20.
Carbon: symbol is C and an atomic number of 6.
Oxygen: symbol is O and an atomic number of 8.
In one molecule of CaCO3, there is one atom of Ca, one atom of C, and three atoms of O as shown by the subscript next to O in the formula. There are no other subscripts to indicate more than one atom of the other elements, so there is only one atom of the other two elements
So there is calcium, symbol is Ca and an atomic number of 20.
Carbon: symbol is C and an atomic number of 6.
Oxygen: symbol is O and an atomic number of 8.
In one molecule of CaCO3, there is one atom of Ca, one atom of C, and three atoms of O as shown by the subscript next to O in the formula. There are no other subscripts to indicate more than one atom of the other elements, so there is only one atom of the other two elements