Electrochemistry Essay

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Electrochemistry is a branch of chemistry which primarily focuses on the flow of electrons and the chemical reactions which occur due to the flow of those electrons. These chemical reactions are known as oxidation-reduction reactions, or simply redox reactions. Electrical energy provides the energy needed for the redox reactions to occur. Where oxidation occurs, reduction is certain to follow. Oxidation entails an increase in oxidation number, signifying a loss of electrons. Reduction entails a decrease in oxidation number, signifying a gain of electrons. A metal could be oxidized or reduced, depending on the products used in the reaction. This can be shown by dividing the net chemical equation into two half-equations: one demonstrating the …show more content…

The substituents were as follows: (1) a copper strip in Cu2+ cation solution, (2) a zinc strip in Zn2+ cation solution, and (3) a lead strip in Pb2+ cation solution. Each metal substituent in their corresponding metal cation solution were placed inside of a test tube, with a small fold of each strip made on the lip of the tube. This created three half cells – one copper, one zinc, and one lead. The circuit was completed by placing each end of a salt bridge (composed of potassium nitrate solidified into gelatinous agar) into two separate half cells containing different metals. The voltage of the voltaic cell was measured with the voltmeter, connecting the alligator leads to each fold of the metal strip on the outer lip of the test tube. Three measurements were taken, time using a new, clean salt bridge. The voltages generated by the Pb/Zn, Pb/Cu, and Cu/Zn cells were recorded and tabulated into figure 1.

As shown in Figure 1, each metal half cell combination included the oxidation of one metal and the reduction of the other. Given that the reduction cell potential of Cu2+ is equal to 0.34 V (Equation 4), the data from Figure 1could be plugged into Equation 5 (manipulated into Equations 6 and 7) to calculate the reduction half cell potentials of zinc (Equation 8) and lead (Equation 9) when combined with copper. The determined values for zinc and lead were, respectively: -0.740 V and -0.145

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