Question

If I have 340 mL of a 1.5 M NaBr solution, what will the concentration be if I add 560 mL water to it?

Answer 1

0.5667 M ≅ 0.57 M.

Step-by-step explanation:

• It is known that the no. of millimoles of a solution before dilution is equal to the no. of millimoles of the solution after the dilution.

• It can be expressed as:

(MV) before dilution = (MV) after dilution.

M before dilution = 1.5 M, V before dilution = 340 mL.

M after dilution = ??? M, V after dilution = 340 mL + 560 mL = 900 mL.

∴ M after dilution = (MV) before dilution/(V) after dilution = (1.5 M)(340 mL)/(900 mL) = 0.5667 M ≅ 0.57 M.