Question

You need 100 mL of a 0.00057 M solution for an experiment. You are given 10 mL of a 5.7 M stock solution. What is the best method to get the final volume and concentration you for trial?

-It is not possible to reach that concentration with the info presented.

-Use a 1.0 mL volumetric pipette and then dilute with water to 100 mL, then repeat serially until the desired concentration is reached.

-Use a graduated cylinder to measure 0.1 mL of the solution and then dilute.

-Use a 10.0 mL volumetric pipette to add all of the solution to 90 mL of water to get the desired concentration.

Answer 1

Given 10 mL of a 5.7 M stock solution.

To make 100ml 0.00057M solution.

The best method to get the final volume and concentration for trial —

Use a 1.0 mL volumetric pipette and then dilute with water to 100 mL, then repeat serially until the desired concentration is reached.

When 1ml of 5.7M is dissolved to make 100ml solution then it become 5.7/100 = 0.057M

Then again when we take 1ml of 0.057M solution and dissolve to make 100ml solution then it become 0.057/100 = 0.00057M which is our required value.