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10.(25 pts) Suppose that soil and groundwater has been contaminated with CCl4 for decades. The site investigation revealed that groundwater has negligible dissolved oxygen, indicating anaerobic conditions. The investigation also revealed that there is negligible amount of organic matter both in ground water and soil. On the other hand, the groundwater showed decent level of nutrients, such as nitrogen and phosphorous. Although you may need more information, you have instinct feeling that this system should be treated biologically by supporting in situ (native) bacteria with injection of an external source of chemical. Let's say that you can choose only one out of the three following chemicals to support the growth of bacteria that is expected to remove CCl4 (i.e., change CCl4 to less chlorinated carbon): 1) O2; 2) hydrogen gas (Hz); or 3) acetic acid (CH3COOH). Demonstrate your choice of the chemical based on the evaluation of thermodynamic potential for the removal of CCl4 with three chemicals. If one (only one) of these three chemicals does not make sense at all as a candidate to be added and you think there is even no worth conducting a thermodynamic potential analysis, indicate which chemical and state very clearly why it is the case. This would mean that you must perform thermodynamic potential analyses for at least two chemicals with CCl4 and choose which one should be added to best support this bioremediation. Half reactions for CCl4, O2, H2, and CH3COOH are available in the appendix of the exam.