In each case, 10.00 mL of the sample solution and 15.00 mL of an organic additive were added to a series of five 50 mL volumetric flasks. The standard Eu(III) or Tb(III) solution (0, 5.00, 10.00, 15.00, and 20.00 mL) was then added to the flasks and they were diluted to 50.0 mL with water. The Eu(III) standards added to the groundwater sample contained 0.185 ng/mL (ppb) of Eu(III). Calculate the concentration of Eu(III) in the groundwater sample.

thats a little if u want the answer just look it up on google thats what i do haha : )

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.