Lecture 34 - 1 36 Step 1 Set-up the cell Measuring K sp...

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

View Full Document Right Arrow Icon

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

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

Unformatted text preview: 4/10/10 1 36 Step 1: Set-up the cell Measuring K sp Pb(s)| Pb 2+ (???? M) || Sn + (1.00 M) | Sn(s) From PbSO 4 (s) Use common-ion: 1.0 M SO 4 2- from Na 2 SO 4 (aq) Half-cell for which we know E o Doesn’t have to be used Cathode (RED CAT) Anode (AN OX) 0.219 V =-0.137 ! 0.0592 2 log 1 1.0 " # $ % & ’ !-0.125 ! 0.0592 2 log 1 [Pb 2 + ] " # $ % & ’ E cell = E C o ! 0.0592 n logQ C " # $ % & ’ ! E A o ! 0.0592 n logQ A " # $ % & ’ Half-rxns as reductions : Solve: [Pb 2+ ] = 1.6 ! 10-8 M 37 Step 2 : Measure cell potential and solve for concentration of metal ion Take potential measurement : E cell = 0.219 V C: Sn 2+ (aq) + 2 e- ! Sn (s) E° = -0.137 V A: Pb 2+ (aq) + 2 e- ! Pb(s) E° = -0.125 V 38 Step 3 : Calculate Ksp using above [Pb 2+ ] PbSO 4 (s) ! Pb 2+ (aq) + SO 4 2- (aq) i. -- c. -- e. -- Know: s = 1.6 ! 10-8 M K sp = [Pb 2+ ][SO 4 2- ] Check assumption... 1.0 +s +s s 1.0 + s Common ion Assume: 1.0 + s " 1.0 = (1.6 ! 10-8 )(1.0) = 1.6 ! 10-8 39 Using that K sp value, can you determine what the cell...
View Full Document

This note was uploaded on 04/22/2010 for the course CHEM 102 taught by Professor Brown during the Winter '10 term at University of Alabama at Birmingham.

Page1 / 2

Lecture 34 - 1 36 Step 1 Set-up the cell Measuring K sp...

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

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