Question

What will be the weight of $CO$ having the same number of oxygen atoms as present in $22\, g$ of $CO_{2}$?

• A. $28\,g$
• B. $22\,g$
• C. $44\,g$
• D. $72\,g$

Answer 1

Answer: (A)

$28\,g$

Answer 2

No. of $O$ atoms in $CO_2 = 2$ Molar mass of $CO_2 = 44\, g$ $44 \,g \equiv 1$ mol $\Rightarrow 22\, g \equiv 0.5$ mol $1$ mole of $CO_2$ contains $= 2 \times 6.023\times 10^{23} O$ atoms $0.5$ mole of $CO_2 = 6.023 \times 10^{23} O$ atoms $1$ mole of $CO = 6.023 \times 10^{23} O$ atoms Mass of $1$ mole of $CO = 12 + 16 = 28\, g$