Experiment #18 Electrochemical Cells

Experiment #18 Electrochemical Cells - ----> Mg...

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

View Full Document Right Arrow Icon
Experiment 18 Electrochemical Cells Part 1: Determine Reduction Potentials Voltage of each half-cell versus the zinc electrode Voltage (V) Anode Cathode Zn vs Ag 1.41 Zn Ag Zn vs Cu 0.98 Zn Cu Zn vs Fe 0.54 Zn Fe Zn vs Mg 0.62 Mg Zn Zn vs Pb 0.47 Zn Pb Reduction Equations for Each Ion Arranged in Decreasing Order of Potential Electrode Potential Accepted Electrode Reduction equation using Zn as the Potentials using (V) 1.41 0.8 0.61 0.98 0.34 0.64 0.54 -0.04 0.58 0.47 -0.13 0.60 0.00 -0.76 0.76 -0.62 -2.07 1.45 Part 2: Measure Cell Potentials Predicted and Measured Cell Potentials: Anode Cathode Equation for the cell reaction Predicted Potential from Experimental Data (V) Mg Cu 1.60 Fe Cu 0.44 Fe Ag 0.87 Mg Pb 1.09 Pb Cu 0.51 Cu Ag 0.43 Mg Ag 2.03 Part 3: Change Ion Concentration 0 M 1.0 M Measured Voltage 0.89 V Calculated Voltage 0.89 V Percent Error 0.13 % Part 4: Find the Solubility Product of AgCl E zn - E o Standard, E zn (V) Hydrogen as Standard, E o (V) Ag + + e - ---> Ag Cu 2+ + 2e - ---> Cu Fe 3+ + 3e - ---> Fe Pb 2+ + 2e - ---> Pb Zn 2+ + 2e - ---> Zn Mg 2+ + 2e
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: ----> Mg Cu 2+ + Mg --> Cu + Mg 2+ 3Cu 2+ + 2Fe --> 3Cu + 2Fe 3+ 3Ag + + Fe --> 3Ag + Fe 3+ Pb 2+ + Mg --> Pb + Mg 2+ Cu 2+ + Pb --> Cu + Pb 2+ 2Ag + + Cu --> 2Ag + Cu 2+ 2Ag + + Mg --> 2Ag + Mg 2+ Zn + Cu 2+--> Zn 2+ + Cu [Zn 2+ ] [Cu 2+ ] Zn + 2Ag +--> Zn 2+ + 2Ag 1.0 V 1.0 V Measured Voltage 0.84 V 1.41 V 2.35E-10 M 1.0 M 2.35E-10 1.80E-10 Percent Error 30.7 % Drops per ml 36 drops/ml 6 M M 1.0 M Measured Voltage 0.40 V 0.98 V 2.54E-20 V 0.00278 M 8.43E+13 2.00E+13 Percent Error 321.36 % [Zn 2+ ] initial [Ag + ] initial E o [Ag + ] [Cl-] (assumption) K sp (experimental) K sp (expected) Part 5: Find the Formation Constant of Cu(NH 3 ) 4 2+ Zn + Cu 2+--> Zn 2+ + Cu [NH 3 ] [Zn 2+ ] initial [Cu 2+ ] initial E o [Cu 2+ ] calculated [Cu(NH 3 ) 4 + ] K f (experimental) K f (expected) Measured Potential (V) 1.51 0.49 0.92 0.99 0.50 0.43 2.02...
View Full Document

This note was uploaded on 06/02/2010 for the course CHEM 104 taught by Professor Any during the Spring '10 term at UNC Charlotte.

Page1 / 4

Experiment #18 Electrochemical Cells - ----> Mg...

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