This green roof on top of Chicago’s City Hall saves the city approximately $5,000 a year in heating and cooling for the building and provides an urban garden space. As plants grow, they release water vapor into the atmosphere around them. How can increasing the coverage of green rooftops in an urban area help to reduce the negative impact of an urban heat island?

definition

                    entropy is a measure of the randomness or the extent of disorder of a chemical process.

                      enthalpy is a measure of the heat change of a reaction occurring at a constant pressure.

measurement units:

                        entropy is measured in joule per kelvin (jk⁻¹)   whereas enthalpy is measured in joule per mole (jmol⁻¹)

requirements:

                            entropy has no requirements or limits, and its change is measured by the division between the heat change of the chemical process and the temperature.

                              in contrast, enthalpy can only be related to the heat change of the reaction under standard conditions.