# How many grams of KCl are needed to make 500 mL of 2.45 M KCl?

May 6, 2016

$91.4$ grams

#### Explanation:

$C = \frac{m o l}{v o l u m e}$

$2.45 M = \frac{m o l}{0.5 L}$

$2.45 M \cdot 0.5 L = m o l$

$m o l = 1.225$

Convert no. of moles to grams using the atomic mass of K + Cl

$1.225 m o l \cdot \frac{\left(39.1 + 35.5\right) g}{m o l}$

$1.225 \cancel{m o l} \cdot \frac{74.6 g}{\cancel{m o l}}$

$= 1.225 \cdot 74.6 g$

$= 91.4 g$