what is Molarity of a solution of 4 moles of NaCl in 2L of water?

To calculate the molarity of a solution, you need to know the amount of solute (in moles) and the volume of the solution (in liters). In this case, you have 4 moles of NaCl and a solution volume of 2 liters.

Molarity (M) is defined as the number of moles of solute per liter of solution. To find the molarity, divide the number of moles by the volume in liters:

Molarity (M) = Moles of solute / Volume of solution

Plugging in the values you have:

Molarity (M) = 4 moles / 2 L

Dividing, you get:

Molarity (M) = 2 M

Therefore, the molarity of the solution is 2 M (2 moles per liter).