Final answer:
The molarity of a NaCl solution where 2 moles of NaCl are dissolved in 0.5 liters of water is 4 M (4 moles per liter).
Step-by-step explanation:
To calculate the molarity of the solution when 2 moles of NaCl are dissolved in enough water to make a final volume of 0.5 liters, you can use the formula for molarity:
Molarity (M) = moles of solute / liters of solution
In this case, the moles of NaCl (solute) are given as 2 moles, and the volume of the solution is 0.5 liters.
Thus, the molarity of the NaCl solution is:
M = 2 moles / 0.5 liters = 4 M
This means the solution's molarity is 4 moles per liter (4 M).