The chemical reaction that causes chromium to corrode in air is given by

4Cr+3O2→2Cr2O3

in which at 298 K

ΔH∘rxn = −2256 kJ
ΔS∘rxn = −549.1 J/K
Part A

What is the standard Gibbs free energy for this reaction? Assume the commonly used standard reference temperature of 298 K.

Express your answer as an integer and include the appropriate units.

Hydroelectricity provides about 7 percent of the electricity generated in the united states. (a) explain how a hydroelectric power plant converts energy stored in water into electricity. (b) identify two factors that determine the amount of electricity that can be generated by an individual hydroelectricity power plant. (c) describe the two main types of land-based hydroelectric power plants. (d) describe two economic advantages and two environmental disadvantages of hydroelectricity.