Hello there, I\'m confused with this post lab assigment and I don\'t know how to

ID: 87943 • Letter: H

Question

Hello there, I'm confused with this post lab assigment and I don't know how to solve it, please help me out if you have an idea about this subject, no need for broad answer, narrow answers will do. Thank you

(I'm not bio major) need someone whos majoring or majored in bio.

Week 2 Post-Lab Questions

For the questions below be sure to show your work as well as the answer to the question.

In this week’s lab you made 100ml of 10x PBS by dissolving 8 g NaCl, 1.2g Na2HPO4 and 0.2 g KH2PO4 in water. You then adjusted the pH to 7.0.

1. How many mg of KH2PO4 did you weigh out?

2. How many liters of 10x PBS did you make?

3. What is the final concentration of NaCl in your solution? (The molecular weight of NaCl is 58.44 g/mol)

4. What is the final concentration of Na2HPO4 in your solution? (The molecular weight of Na2HPO4 is 141.96 g/mol)

5. What is the final concentration of KH2PO4 in your solution? (The molecular weight of KH2PO4 is 136.1 g/mol)

6. What is the hydrogen ion concentration of your solution (pH=7.0)?

7. If the initial pH of your solution was 6.29 would you need to add an acid or a base to adjust the pH of a solution to pH 7.0?

10x PBS is a concentrated stock solution that is used to make more dilute solutions of PBS. Starting with your 10xPBS stock solution, how would you make the following solutions?

8. 100 mls of 1xPBS

9. 30 mls of 3xPBS

10. 1 l of 0.1xPBS

Explanation / Answer

Answer: