# How many copper atoms in a 860*kg mass of the metal?

Aug 28, 2017

A lot, we assess the molar quantity......

#### Explanation:

Copper has a molar mass of $63.55 \cdot g \cdot m o {l}^{-} 1$. What does this mean? It means that ${N}_{A}$, $\text{Avogadro's number}$, i.e. $6.022 \times {10}^{23}$ individual copper atoms have a mass of $63.55 \cdot g$. And if you can get your head around this, that the mole is simply a NUMBER, it will save you a lot of angst. This is the principle of chemical equivalence: a mass represents a numerical quantity of atoms or molecules. And we can use masses to determine stoichiometric equivalence in chemical equations.

And so here, we gots an $860 \cdot k g$ mass of copper......and so we take the product.....

$\frac{860 \cdot k g \times {10}^{3} \cdot g \cdot k {g}^{-} 1 \times 6.022 \times {10}^{23} \cdot \text{copper atoms} \cdot m o {l}^{-} 1}{63.55 \cdot g \cdot m o {l}^{-} 1}$

$= \text{an absurdly large number of copper atoms......}$