Consider the reaction 4FeS2 + 11O2 → 2Fe2O3 + 8SO2. If 8 moles of FeS2 react with 15 moles of O2, what is the limiting reactant? a

FeS2

b

Fe2O3

c

O2

d

SO2

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.