Suppose solute a has a distribution coefficient of 1.0 between water and diethyl ether. demonstrate that if 100 ml of a solution of 5.0g of a in water were extracted with two 25ml portions of ether, a smaller amount of a would remain in the water than if the solution were extracted with one 50-ml portion of ether.

Explained

Explanation:

a) performing extraction of 25 ml of ether each time

K= 1=

solving we get x= 4 g dissolved in water

5-x=1 g dissolved in ether

second extraction

K= 1 =

solving this we get x= 3.2g dissolved in water

4-x= 3.2 g dissolved in ether

combining the two extractions 0.97 g of A extracted into ether that is 97% is extracted

b) performing one extraction 50% ether

distribution coefficient , K is the concentration of solute dilute to that to the solvent water

K= 1.0=

solving we get

x= 3.33 g dissolved in water

and 5-x= 1.67 dissolved in ether

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.