Question

If 5.00 g of sodium chloride is dissolved in 20.0 mL of solution at room temperature, is the solution saturated,supersaturated, or unsaturated? (The molarity of a saturated NaCl solution at room temperature is 5.98 M.)

Answer 1

First, we need to calculate the molarity of the solution:

Molarity = moles of solute / liters of solution

We know the mass of solute (5.00 g) and the volume of solution (20.0 mL = 0.0200 L). To find the moles of solute, we need to divide the mass by the molar mass of NaCl:

moles of NaCl = 5.00 g / 58.44 g/mol = 0.0855 mol

Now we can calculate the molarity:

Molarity = 0.0855 mol / 0.0200 L = 4.28 M

The molarity of the solution is less than the molarity of a saturated NaCl solution at room temperature (5.98 M), so the solution is unsaturated.