Which of the following solutions has the highest salt concentration?

• A. A solution containing 10 g of NaCl dissolved in 200 mL of water
• B. A solution containing 5 g of NaCl dissolved in 100 mL of water
• C. A solution containing 10 g of NaCl dissolved in 100 mL of water
• D. A solution containing 5 g of NaCl dissolved in 200 mL of water

Answer: (C)

Verified step by step guidance

1. Identify that the problem is asking for the solution with the highest salt concentration, which means we need to compare the concentration of NaCl in each solution.
2. Recall that concentration (specifically molarity) is defined as the number of moles of solute divided by the volume of the solution in liters: \(\text{Molarity} = \frac{\text{moles of solute}}{\text{volume of solution in liters}}\).
3. Calculate the moles of NaCl in each solution by using the molar mass of NaCl (approximately 58.44 g/mol): \(\text{moles} = \frac{\text{mass of NaCl (g)}}{58.44}\).
4. Convert the volume of water given in milliliters to liters by dividing by 1000: \(\text{volume (L)} = \frac{\text{volume (mL)}}{1000}\).
5. For each solution, compute the molarity by dividing the moles of NaCl by the volume in liters, then compare these values to determine which solution has the highest salt concentration.