Question

The mass in grams of a single chlorine atom and of a single molecule of $O_2$ is :

• A. $5.89\times {10}^{-23}g/atom,5.31\times {10}^{-23}g/molecule$
• B. $8.81\times {10}^{-23}g/atom,4.31\times {10}^{-23}g/molecule$
• C. $5.81\times {10}^{-25}g/atom,5.31\times {10}^{-25}g/molecule$
• D. None of the above
  

Answer 1

The correct option is A $5.89\times {10}^{-23}g/atom,5.31\times {10}^{-23}g/molecule$

Mass of one Cl atom is 35.5 gm
So one atom of Cl contains mass in gm/atom $=\frac{35.5}{6.023\times {10}^{23}}$
$=5.89\times {10}^{-23}$ g/atom

Mass of one molecule of oxygen is$16\times 2$ is $32$ gm
So one molecule of oxygen contains mass in gm/atom $=\frac{32}{6.023\times {10}^{23}}$
$=5.31\times {10}^{-23}$ g/atom