Moles, Molar Mass, and Molarity│Please Help!

Question

What is the molarity of a 0.500L solution that contains 2.0 moles of NaCl?

1. 4.0M
2. 250M
3. 1.0M
4. 2.0M

Answer 1

Molarity is defined as moles of solute per liter of solution.

How many moles of solute do we have? Answer = 2.0 moles NaCl

How many liters of solution do we have? Answer = 0.500 liters

What is the molarity? Answer = 2.0 moles / 0.500 liters = 4.0 moles / liter = 4.0 molar = 4.0 M