Question

You conduct a trial of the experiment as described in the lab. The molarity of the sodium hydroxide stock solution is 0.074 M. You mix the crystal violet and sodium hydroxide as described on page 6 of the experiment. What is the concentration of sodium hydroxide in the mixed solution right before the reaction starts?

*Empty the cuvette and dry it thoroughly inside and out with a KimWipe. Using the buret
provided, dispense 9.00 mL of 1.5 x 10-5 M crystal violet solution into a clean, dry 50 mL
beaker. Using a calibrated plastic syringe, add 1.0 mL of 0.050 M NaOH to the CV solution
as rapidly as possible without splashing. At the same instant of NaOH addition, click the
green Collect icon from the toolbar to start the reaction timer.*

Answer 1

Answer:

0,0074M

Explanation:

In the experiment, you are mixing 9,00 mL of a crystal violet solution, then, you add 1,0 mL of the NaOH solution for a total volume of 10,0 mL.

Now, if you add 1,0mL of NaOH 0,074M, and total volume of the solution change to 10,0 mL, the NaOH concentration in the solution will be:

0,074M ×(1,0 mL / 10,0 mL ) = 0,0074M

I hope it helps!