ExtraCreditHomework1_KEY

# ExtraCreditHomework1_KEY - Name KEY EID Extra Credit...

This preview shows pages 1–4. Sign up to view the full content.

Name: KEY EID: Extra Credit Homework #1 Complete questions below and hand in to a TA by the end of class, Friday, Sept. 2. 1. Draw the structures of the 20 amino acids (in their predominant form at pH 7.0, clearly showing stereochemistry). Indicate the pK a of any side chain that is ionizable. Also provide the three-letter and one-letter codes.

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
What is a pirate’s favorite amino acid? Arginine! 2. A 1.0 L solution has a mixture of 0.05 M NaH 2 PO 4 (pK a = 6.86) and 0.10 M Na 2 HPO 4 . How much 1.0 M NaOH should be added to bring the solution to pH 7.4? pH = p K a + log([A - ]/[HA]) 7.4 = 6.86 + log([A - ]/[HA]) [A - ]/[HA] = 10 0.54 = 3.47 3.47 = (A - + x)/(HA – x) = (0.10 + x)/(0.05 – x) 0.174 – 3.47x = 0.10 + x x = 0.017 mol 0.017 mol · 1 L/mol = 0.017 L or 17 mL of 1.0 M NaOH
3. Taxol exhibits antitumor activity. Label the indicated functional groups. 1. Hydroxyl 2. Ester 3. Amide 4. Ether 5. Keto (carbonyl) 4. Draw out each of these peptides as they exist at the indicated pH (show stereocenters). Indicate the net charge of each peptide at that pH. Also provide the approximate pI for each peptide.

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### What students are saying

• As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

Kiran Temple University Fox School of Business ‘17, Course Hero Intern

• I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

Dana University of Pennsylvania ‘17, Course Hero Intern

• The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

Jill Tulane University ‘16, Course Hero Intern