Question

The weight of a single atom of oxygen is :

• A. $0.057\times 10^{23}g$
• B. $2.657\times 10^{-23}g$
• C. $2.657\times 10^{23}g$
• D. $4.657\times 10^{-23}g$

Answer 1

Answer: (B)

Atomic mass $=$ Avogadro number
$6.023\times 10^{23}$ atoms of $O_2$ is present in $=16g$
$\therefore 1$ atoms of $O_2$ is present in
$=\frac{16}{6.023\times 10^{23}}$
$=2.66\times 10^{-23}g$