Chem 2080 Lab report exp 5

Chem 2080 Lab report exp 5 - Preparing a Buffer Solution By...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
Preparing a Buffer Solution By Molly McMahon Lab Instructor: Megan Kopp March 19, 2010 Desk 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
Purpose A buffer solution with a certain pH and approximate volume of 400mL was prepared. This buffer had the capacity to absorb 20 mL of either .02M HCL or .02 NaOH, and underwent a pH change of no more than + or - 0.1. Materials and Equipment Ÿ 400 mL of C 3 H 4 N 2 Ÿ 25 mL of .02M HCL or .02M NaOH (in some trials NaOH was used, which raised pH; and in others, HCl was used, which lowered pH) Ÿ Beaker for mixing solution Ÿ PH meter Ÿ Balance to weigh out C 3 H 5 N 2 Cl (according to calculations, .753g of C 3 H 5 N 2 Cl would be the ideal amount to change our pH by no more than .1) Calculations K a = 1.0 x 10 -14 = 1.11 x 10 -7 9.0 x 10 -8 6.7= -log(1.11 x 10 -7 ) + log( [C 3 H 4 N 2 ] / [C 3 H 5 N 2 Cl ] ) 6.7= 6.95 + log( [C 3 H 4 N 2 ] / [C 3 H 5 N 2 Cl ] ) 6.7-6.95= log( [C 3 H 4 N 2 ] / [C 3 H 5 N 2 Cl ] ) -.25= log( [C 3 H 4 N 2 ] / [C 3 H 5 N 2 Cl ] ) 10 -.25 = ( [C 3 H 4 N 2 ] / [C 3 H
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 03/31/2010 for the course EN 102 taught by Professor Graves during the Spring '10 term at Acadia.

Page1 / 4

Chem 2080 Lab report exp 5 - Preparing a Buffer Solution By...

This preview shows document pages 1 - 3. Sign up to view the full document.

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