4. In a well-written essay, explain how urban heat islands might be contributing to global warming. Use specific examples from the article. Then, describe some possible solutions to the problem and weigh the merits of these solutions, including possible costs and benefits. The article is https://www. nationalgeographic. org/encyclopedia/urban-heat-island/

Solid tin exists in two forms: white and gray. for the transformation sn(s, white) → sn(s, gray) the enthalpy change is -2.1 kj/mol and the entropy change is -7.4 j/(mol*k). a. calculate the gibbs free energy change for the conversion of 1.00 mol white tin to gray tin at -30℃. b. will white tin convert spontaneously to gray tin at -30℃? c. at what temperature are white and gray tin thermodynamically equivalent at a pressure of 1 atm?