Question

In the lab you take 50.0 mL of a 40.0 M NaOH solution and then add water to it until it reaches the 500.0 mL mark of the flask. What is the concentration of the new solution?

Answer 1

4.00M NaOH

Step-by-step explanation:

A 50-ml amount of 40.0M NaOH contains

(40.0 mol NaOH/1 L)×(0.0500L) = 2.00 mol NaOH

Adding enough water to make a 500.0 mL NaOH solution, the new concentration of this solution is

2.00 mol NaOH/0.5000 L = 4.00M NaOH