# A 5.67*g mass of chromium metal represents what molar quantity?

May 9, 2016

$\text{Moles" = "Mass"/"Molar Mass}$
$\text{Moles of Chromium" = "Mass of chromium"/"Molar mass of chromium}$
$=$ $\frac{5.67 \cdot g}{51.99 \cdot g \cdot m o {l}^{-} 1}$ $=$ $0.109 \cdot m o l$
So what is a mole? It is simply a number, $6.022 \times {10}^{23}$. It is a fact that $\text{Avogadro's number}$ of chromium atoms have a mass of $51.99 \cdot g$. Thus $\text{Avogadro's number}$, ${N}_{A}$, is the link between the micro world of atoms and molecules, to the macro world of grams and litres, that which we can suitably measure in a lab.