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An al/al3 concentration cell is constructed in which both electrodes are aluminum the al 3 concentrations in the electrolyte are 0.01 m for half cell 1 and 0.9 m for half cell 2 and the operating temperature is 10 c.

a. write the reactions for each half cell
b. calculate the voltage generated by this concentration cell which electrode will corrode

User Ekhanna
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Final answer:

A concentration cell is constructed using aluminum electrodes with different concentrations of Al3+ in the electrolyte. The half-reactions for the corresponding half cells can be written, and the voltage can be calculated using the Nernst equation. The electrode in Half Cell 2, which has a higher concentration of Al3+, will corrode.

Step-by-step explanation:

A concentration cell is constructed by connecting two nearly identical half-cells, each based on the same half-reaction and using the same electrode, varying only in the concentration of one redox species. In this case, both electrodes are aluminum. The half-reactions for the half-cells can be written as:

Half Cell 1: Al(s) -> Al3+ (aq, 0.01 M) + 3e-

Half Cell 2: Al(s) -> Al3+ (aq, 0.9 M) + 3e-

To calculate the voltage generated by the concentration cell, you can use the Nernst equation:

Voltage = (RT/nF) * ln([Al3+ in Half Cell 2]/[Al3+ in Half Cell 1])

Where R is the gas constant, T is the temperature in Kelvin, n is the number of electrons transferred in the reaction, and F is Faraday's constant. Plugging in the values from the question, you can calculate the voltage.

Regarding which electrode will corrode, in a concentration cell, the electrode with the higher concentration of the redox species will corrode. In this case, since the concentration of Al3+ is higher in Half Cell 2 (0.9 M), the electrode in Half Cell 2 will corrode.

User Dilbert
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