Question

Find the number of oxygen atoms in 88g of ${CO}_2$ ?

• A. $2.4092\times {10}^{24}$
• B. $2.4092\times {10}^{23}$ ​
• C. $2409.2\times {10}^{24}$ ​
• D. $24.092\times {10}^{24}$ ​

Answer 1

The correct option is A

$2.4092\times {10}^{24}$

Molar mass of ${CO}_2$ = 44 g/mol
Number of moles of CO₂ present in 88g of ${CO}_2$ = $\frac{88}{44}$ = 2 moles
1 mole of ${CO}_2$ contains 2 moles of oxygen atoms.
2 moles of ${CO}_2$ contains 4 moles of oxygen atoms
1 mole of oxygen contains $6.023\times {10}^{23}$ atoms of oxygen
4 moles of oxygen contains = $4\times 6.023\times {10}^{23}$
= $24.092\times {10}^{23}$
= 2.4092 X ${10}^{24}$ atoms of oxygen

Therefore, 88g of ${CO}_2$ contains $2.4092\times {10}^{24}$ atoms of oxygen