Four beakers each contain a different aqueous solution: Beaker A has 0.5 mol NaCl dissolved in 1.0 L of water, Beaker B has 1.0 mol NaCl dissolved in 2.0 L of water, Beaker C has 0.25 mol NaCl dissolved in 0.5 L of water, and Beaker D has 2.0 mol NaCl dissolved in 4.0 L of water. Which beaker has the highest molarity?

• A. Beaker C
• B. Beaker A
• C. Beaker D
• D. Beaker B

Answer: (A)

Verified step by step guidance

1. Recall that molarity (M) is defined as the number of moles of solute divided by the volume of the solution in liters. The formula is: \(M = \frac{\text{moles of solute}}{\text{volume of solution in liters}}\).
2. Calculate the molarity for each beaker by dividing the moles of NaCl by the volume of water in liters:
3. - Beaker A: \(M_A = \frac{0.5}{1.0}\)
4. - Beaker B: \(M_B = \frac{1.0}{2.0}\)
5. - Beaker C: \(M_C = \frac{0.25}{0.5}\)
6. - Beaker D: \(M_D = \frac{2.0}{4.0}\).
7. Compare the calculated molarities for all four beakers to determine which one has the highest value.
8. Identify the beaker with the highest molarity as the one with the greatest concentration of NaCl in solution.