# How many atoms in a 10*mol quantity of CaCl_2?

Jul 18, 2017

How many?

#### Explanation:

If I have 12 dozen eggses, how many dozens do I have? Do you agree that it is one dozen? Well then how many eggs in 12 dozen?

Now we gots a $10 \cdot m o l$ quantity of $C a C {l}_{2}$, i.e. there are $10 \cdot m o l \times {N}_{A}$ individual formula units of $C a C {l}_{2}$, where ${N}_{A} \equiv \text{Avocado number} \equiv 6.022 \times {10}^{23} \cdot m o {l}^{-} 1$. And I am perfectly at liberty to use the symbol ${N}_{A}$ to represent that number.

And so we got $10 \times {N}_{A} = 6.022 \times {10}^{24}$ individual calcium ions.

And we also gots $2 \times 10 \times {N}_{A} = 12.044 \times {10}^{24}$ individual chloride ions.

Can you tell me what mass of $C a C {l}_{2}$ we got?