Question

Calculate the number of oxygen atoms and its mass in 50g of CaCo3​

Answer 1

The number of oxygen atoms = 3

Mass = 24 g

Further explanation

The formula of a compound shows the composition of the constituent elements

CaCO₃ is composed of 3 types of elements, namely Ca, C and O

The amounts of each of these elements in the compound CaCO₃:

• Ca = 1
• C = 1
• O = 3

So the number of oxygen atoms = 3

mass of Oxygen :

$\tt mass~O=\dfrac{3\times Ar~O}{MW~CaCO_3}\times mass~CaCO_3\\\\mass~O=\dfrac{3\times 16}{100}\times 50=24~g$