A tank contains 10 liters of pure water. A solution of an unknown, but constant concentration of salt is flowing in at 0.5 liters per minute. The water is mixed well and drained at 1 liter per minute. After 20 minutes there are 10 grams of salt in the tank. (i) Give an adequate mathematical model for this scenario. Explain what each of your variables means. (ii) What is the concentration of the incoming salt solution

i) ∴∫  = ∫ ------ ( 1 )

ii) C = 4.303

Explanation:

Given data:

water in tank = 10 liters

concentration of salt flowing in = 0.5 liters/min

10 grams of salt is left in tank after 20 minutes

mixed water is drained at 1 liter per minute

i) Adequate mathematical model for the scenario

lets assume ; A( t ) amount of salt after t minute

A( t ) = 10grams   where t = 20 minutes

differentiate A(t)

dA / dt = ( rate in ) - ( rate out )

           = 0.5 * 0  - A/10

∴∫  = ∫ ------ ( 1 )

ii) hence;  In A =  -----  ( 2 )

at  t = 20 , A = 10grams

find C = In 10 + 2

          = 2.303 + 2 = 4.303

back to ( 2 )

In A =

∴ A = e

increased stability in the completion of fluorine's outer shell.

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.