Electrochemical Cell Experiment

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In this experiment, various electrochemical cells were measured and calculated to determine their electrical cell potential. In the electrochemical cell Zn (s) │Zn2+ (0.10 M) ││ Cu2+ (0.10 M) │ Cu(s), E cell potential was determined to be 1.040 V while the standard E˚ cell potential was 1.10 V. In the electrochemical cell Zn (s) │Zn2+ (0.10 M) ││ Cu2+ (1.0 M) │ Cu(s) E cell potential was determined to be 1.060 V while the standard E˚ cell potential was 1.10 V. In the electrochemical cell Cu (s) │Cu2+ (0.010 M) ││ Cu2+ (1.0 M) │ Cu(s), E cell potential was determined to be 0.032 V while the standard E˚ cell potential was 0.00 V. The E cell value in the electrochemical cell Cu (s) │Cu2+ ( M ) ││ Cu2+ ( M) │ Cu(s) was determined …show more content…
In the cell Cu (s) + Cu2+(aq) ↔ Cu2+ + Cu(s) ,when the concentration of Cu2+ was reduced from 1.0 M to 0.010 M, it caused the reaction to shift to the right. The standard E value was 0.00 Volts, the reaction shifted right and so did the E cell value. It got higher than the standard value as it attempts to reestablish equilibrium. According to LeChatliers principle, “When any system at equilibrium is subjected to change in concentration, temperature, volume, or pressure, then the system readjusts itself to counteract (partially) the effect of the applied change and a new equilibrium is established”. In the cell Zn (s) + Cu2+(aq) ↔ Zn2+ + Cu(s), as the concentration Cu2+ was increased from 0.10 M to 1.00 M, this caused the reaction to shift right and thereby increasing the cell potential of cell 2 from 1.10 to 1.13 Volts. Electrical potential depends upon the concentrations of the substances, the temperature, and the pressure, as these stated factors increase beyond standard values, so does electrical potential of the …show more content…
These errors may range from human errors to equipment errors. Internal resistance within the voltmeter may cause a reduction in measured voltage values thereby giving voltage results that are too low or too high. These result influence the overall E cell value rendering results incorrect. Corrosion on the alligator clip that was used could prevent consistent contact of the electrode thereby giving fluctuating results throughout the experiment. Electrode touching the salt bridge in the beaker while a measurement was taken can also influence the measured voltage by the voltmeter. Mix matching the voltmeter clips to the wrong electrode will possibly yield wrong negative values thereby indicating non-spontaneity of the reaction. Human errors due to inability to read a measuring instrument, insufficient data collection, and observer misinterpretation can invariably influence the overall accuracy of the experiment. A salt bridge keeps charges from accumulating on one side or the other, thus maintaining charge neutrality. Failure to attach a salt bridge to each half cell causes the solution in the anode compartment to be positively charged and the solution in the cathode compartment would become negatively charged, because of the charge imbalance the electrode reaction would quickly come to a halt. Precision of this experiment could not be evaluated because the experiment was carried out

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