Key Quiz 9 09-106 S 11

# Key Quiz 9 09-106 S 11 - this buffer. (2 points) 4. A...

This preview shows pages 1–2. Sign up to view the full content.

Name ______________________________ _ Quiz 9 (10 points) 09-106 Spring 2011 Recitation ( CIRCLE ONE TA and ONE TIME ): Christian Steve Brendan 6:30 7:30 4/7/11 (10 minutes allowed) In order to ensure the maximum amount of partial credit on short problems, please show all work and clearly circle your final answers. A periodic table, constants, equations, and a table of weak acid constants are on the attached page (front and back). You may detach and keep this page. 1. Calculate the pH at the equivalence point in the titration of 50.0 mL of 2.0 M KBrO(aq) with 2.0 M HBr(aq). (4 points) 2. Circle below the pair of species that is a buffer solution. (1 point) HCl and KCl LiH 2 PO 4 and Li 2 HPO 4 KOH and H 2 O 3. You want to make a buffer having a pH of 8.0. Using the table of acids on the attached page, write the formulas of both the acid and its conjugate sodium salt that would yield the best buffer capacity for

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.

Unformatted text preview: this buffer. (2 points) 4. A solution containing both C 5 H 5 N(aq) ( K b = 1.7 x 10-9 ) and C 5 H 5 NHNO 3 (aq) has a pH of 5.0. (a) Circle below the substance that is in greater abundance. [Support your answer with a calculation]. C 5 H 5 N C 5 H 5 NH + (2 points) (b) The pH of the above solution is more resistant to change upon the addition of small amounts of strong ( ACID , BASE ) ( Underline one ) (1 point) Name ______________________________ _ Quiz 9 (10 points) 09-106 Spring 2011 Recitation ( CIRCLE ONE TA and ONE TIME ): Christian Steve Brendan 6:30 7:30 4/7/11 (10 minutes allowed) pH = -log[H 3 O + ] pOH = -log[OH-] pH + pOH = 14 [H 3 O + ][OH-] = 1.0 x 10-14 (@25°C) K a K b = 1.0 x 10-14 pK a = -log K a pK b = -log K b pH = pK a + log{ [base] / [acid] } [base]/[acid] = 10 pH - pKa...
View Full Document

## This note was uploaded on 09/29/2011 for the course CHEMISTRY 09-106 taught by Professor Vuocolo during the Fall '09 term at Carnegie Mellon.

### Page1 / 2

Key Quiz 9 09-106 S 11 - this buffer. (2 points) 4. A...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online