What is the molarity of a 2.0L solution that was made up with 4.0 moles of NaCl?

[NaCl]: 2M

Explanation:

This solution is made of NaCl therefore:

Our solute is NaCl

Moles of solute: 4

Our solution's volume is 2L

Molarity are the moles of solute contained in 1L of solution (mol/L)

[NaCl]: 4 mol / 2L = 2M

We can also make a rule of three:

In 2 L we have 4 moles of solute

So, In 1 L we must have (1. 4) / 2 = 2 M