Answer:
Step-by-step explanation:
When the 500.0 mL of 0.20 M phosphoric acid is added to 1.00 L of water, the total volume of the resulting solution becomes:
500.0 mL + 1000.0 mL = 1500.0 mL = 1.5 L
The number of moles of phosphoric acid in the solution is:
moles of H3PO4 = Molarity × volume in liters
moles of H3PO4 = 0.20 M × 0.500 L = 0.100 mol
The molarity of the resulting solution is then:
Molarity = moles of solute ÷ volume of solution in liters
Molarity = 0.100 mol ÷ 1.5 L = 0.067 M
Therefore, the molarity of the resulting solution is 0.067 M.