Question

What is the percent composition of each element in CaCO 3 ? ( Mass of Element divided by mass of Compound) x 100

Answer 1

Since we're sticking with theoretical values instead of experimental, Percent Composition would be (Molar Mass of the element) / (Molar mass of compound) x 100%

Molar mass of Calcium: 40g/mol

Molar mass of Carbon: 12g/mol

Molar mass of Oxygen: 16g/mol

Molar mass of CaCO3 (Calcium Carbonate) = (40) + (12) + (16)*3 = 100g/mol

Percentage composition of Calcium =
`(40)/(100) \ * \ 100 =` 40% of Calcium

Percentage composition of Carbon =
`(12)/(100) \ * \ 100 =` 12% of Carbon

(For the next one, there are 3 oxygen, so it'd be 16x3 = 48g/mol)

Percentage composition of Oxygen =
`(48)/(100) \ * \ 100 =` 48% of Oxygen

Answer 2

molar mass of CaCO3=40+12+3(16)

=100 gmol-1

Ca percent composition=40/100*100%

=40%

C percent composition=12/100*100%

=12%

0 percent composition=48/100*100%

=48%