Assignment2

Assignment2 - 0.200 M solution of the basic alanine (L-) ?...

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

View Full Document Right Arrow Icon
Analytical Methods (CHEM 207) Assignment 2: Wednesday, October 13, 2010 Due Date: Wednesday, October 20, 2010 Name:____________________________________ Show all your work clearly. Use K w = 1.0 ×10 -14 where necessary. Give answers to correct number of SFs. 1. (a) The neutral form of alanine can be represented as HL . Starting with the fully protonated form (H 2 L + ) , write all the possible acid dissocation equilibria and show the corresponding K a and K b -values. ( This data can be found on page 182 of your text ) ( 3 pts ) (b) Given a solution containing 0.10 M H 2 L + , use the equilibria above to calculate concentrations of each of the species ([H 2 L + ], [HL], [L - ], [H + ] and [OH - ]) . ( 5 pts ) (c) What would be the pH of a
Background image of page 1

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

View Full DocumentRight Arrow Icon
Background image of page 2
Background image of page 3

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

View Full DocumentRight Arrow Icon
Background image of page 4
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: 0.200 M solution of the basic alanine (L-) ? ( 2 pts ) 2. (a) Draw and label the (i) acidic , (ii) zwitterionic , and (iii) basic form of Glycine. (3 pts) (b) Given a 200.0 mL solution of 0.200 M of the acidic glycine , calculate the pH after addition of (i) 0.00 mL of 1.00 M NaOH (2 pts) (ii) 200.00 mL of 0.500 M NaOH (2 pts) (c) What volume of 0.500 M NaOH must be added to reach a pH equal to (i) pK a1 ? ( 2 pts ) (ii) pK a2 ? ( 2 pts ) (iii) 10.00? ( 2 pts ) 3. How many moles Na 2 CO 3 ( MW 105.99) would be added to 5.00 grams of NaHCO 3 (MW 84.01) to produce 200.0 mL of a buffer at pH = 10.00 ? (pK a1 = 3.60, pK a2 =10.33) ( 2 pts )...
View Full Document

Page1 / 4

Assignment2 - 0.200 M solution of the basic alanine (L-) ?...

This preview shows document pages 1 - 4. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online