Question

1 atom of Iron $\left(Fe\right)$ weighs ______ grams.

(Molecular Weight of $Fe=56$ g/mole)

• A. $9.3\times {10}^{-23}$
• B. $6.3\times {10}^{-23}$
• C. $5.3\times {10}^{-23}$
• D. $4.3\times {10}^{-23}$

Answer 1

The correct option is A $9.3\times {10}^{-23}$

For $Fe$ atoms molar mass $=56$ g/mole.

$1$ mole $={6.023\times 10}^{23}$ atoms

$56$ g $={6.023\times 10}^{23}$ atoms

$1$ atom weighs =$\frac{56}{{6.023\times 10}^{23}}$ g $=9.3\times {10}^{-23}$ g