A student is told to use 20.0 grams of sodium chloride to make an aqueous solution that has a concentration of 10.0 grams of sodium chloride per liter of solution.Assuming that 20.0 grams of sodium chloride has a volume of 7.5 milliliters,about how much water will she use in making this solution?
A)9.25 L
B)9.5 L
C)9.9925 L
D)10 L

Question

Quizplus · Accepted Answer

To make a solution with a concentration of 10.0 grams of sodium chloride per liter of solution, we need to dissolve 20.0 grams of sodium chloride in:

20.0 g NaCl / 10.0 g/L = 2.0 L

However, we need to subtract the volume of the sodium chloride itself from the total volume of the solution. We know that 20.0 g of NaCl has a volume of 7.5 mL, so:

2.0 L - 0.0075 L = 1.9925 L = 1992.5 mL

Therefore, the student will use about 1992.5 mL or 9.9925 L of water to make the solution. The closest answer choice is C: 9.9925 L.

A Student Is Told to Use 20