50 mL of 0.2 mol/L NaCl solution is mixed with 150 mL of 0.5 mol/L NaCl solution. What is the concentration of the mixture?

Answer and explanation

Correct answer: A. 0.425 mol/L

  1. Step 1: Total amount (mol, volumes in litres).
  2. Step 2: Concentration mol/L.
Answer
0.425 mol/L.
Why not the others: 0.35 mol/L: the two concentrations are averaged without weighting by volume. 0.7 mol/L: the concentrations are added. 85 mol/L: the total amount is not divided by the total volume.

Practise more Solutions.

Free questions with an explanation for every one, and full timed EJU Japan mock tests.