# What is the mass in grams of 5.56 X 10^22 lead atoms?

Jan 25, 2017

Well, $6.0221 \times {10}^{23}$ individual lead atoms have a mass of $207.2 \cdot g$.

#### Explanation:

So we take the quotient,

$\left(5.56 \times {10}^{22} \text{ atoms")/(6.022xx10^23*"atoms} \cdot m o {l}^{-} 1\right)$ $\times 207.2 \cdot g \cdot m o {l}^{-} 1$ $=$

$\text{How many grams?}$

This idea of mass equivalence, of a mass representing a GIVEN number of atoms or molecules, is central to chemistry, and it is worth getting right. Using this concept, for a given reactant, we can predict the mass of products likely to be observed. Over your studies in chemistry, you will do many such problems.