# Question #fc5c1

Nov 7, 2017

$33$ grams.

#### Explanation:

Given:

$\text{volume = 100 mL = 0.100 L}$

$\text{concentration = 2.5 mol/L}$

The volume and concentration of a substance are related to the number of moles by the equation

$n = c V$

where $n$ is the number of moles, $c$ is the concentration, and $V$ is the volume of the substance.

The number of moles of a substance is related to its mass by the equation

$m = n M$

where $m$ is the mass, $n$ is the number of moles, and $M$ is the molar mass of the substance.

Find the number of moles of solution using the first equation:

$n = c V$

$n = \left(2.5 \text{mol"/"L")("0.100 L}\right)$

$n = \text{0.25 mol}$

Find the mass using the second equation:

$m = n M$

$m = \left(\text{0.25 mol")(132.14 "g"/"mol}\right)$

$m = \text{33 g}$