# A chemist obtains 2.50 moles of sodium nitrate (NaNO_3). What is the mass of this sample?

## The molar masses for the elements are Na = 23.0 g, N = 14.0 g, and O = 16.0 g.

Mar 26, 2017

#### Explanation:

You are given $\text{2.50 moles}$ of sodium nitrate, $\left(N a N O 3\right)$.

Given moles, now, you are to convert back to mass (in grams).

To do this, you need to set up the problem as follows:

First, find the formula mass of the compound using the periodic table.

$N a = 23 g$
$N = 14 g$
$O = 16 g \cdot 3 = 48 g$

Total = 85 grams

So, for every $1 \text{mole}$ of $N a N {O}_{3}$, you have 85 grams.

We will set up a conversion factor to solve for mass in grams of the sample using moles of $N a N {O}_{3}$.

(2.50 cancel"moles")/1 * (85color(white)(.)"grams")/(1 cancel"mole") = "212.5 grams"

Answer: 212.5 grams of $N a N {O}_{3}$