If you have 2.4 xx 10^24 atoms of copper, how many moles of copper do you have?

Jun 20, 2018

Well what is the $\text{Avocado number}$?

Explanation:

This is given as supplementary material in every chemistry and fyzics exam you sit...

${N}_{\text{Avocado}} = 6.022140857 \left(74\right) \times {10}^{23} \cdot m o {l}^{-} 1$...and please note the units...

And so we take the quotient...

$\frac{2.4 \times {10}^{24} \cdot \text{copper atoms}}{6.022140857 \left(74\right) \times {10}^{23} \cdot m o {l}^{-} 1}$

$= 3.99 \cdot m o l \cdot \text{copper atoms}$...a mass of approx. $250 \cdot g$...how did I know that?