What mass of (solid) LiCl is needed to prepare 200. mL of 0.40 M solution?

Answer 1

First, let us find the molecular weight of LiCl. It is equal to 42.4 g/mol.

Now let us convert 200. mL = 0.200 L of the solution to grams of LiCl using the concentration (mol/L) and molecular weight (g/mol) as conversion factors as follows

0.200 L x 0.40 mol/L x 42.4 g/mol = 3.4 g LiCl

I left two significant figures in the answer in order to match the number of significant figures in 0.40 M