Hydrothermal vents deep on the ocean oor spout water at

Chapter 12, Problem 12.62

(choose chapter or problem)

Hydrothermal vents deep on the ocean oor spout water at temperatures as high as 570C. This temperature is below the boiling point of water because of the immense pressure at that depth. Since the surrounding ocean temperature is at 4.0C, an organism could use the temperature gradient as a source of energy. (a) Assuming the specic heat of water under these conditions is 1.0 cal/gC, how much energy is released when 1.0 liter of water is cooled from 570C to 4.0C? (b) What is the maximum useable energy an organism can extract from this energy source? (Assume that the organism has some internal type of heat engine acting between the two temperature extremes.) (c) Water from these vents contains hydrogen sulde (H2S) at a concentration of 0.90 mmole/liter. Oxidation of one mole of H2S produces 310 kJ of energy. How much energy is available through H2S oxidation of 1.0 L of water?