Bromine (br2) is produced by reacting hbr with o2, with water as a byproduct. the o2 is part of an air (21 mol % o2, 79 mol % n2) feed stream that is flowing sufficiently fast to provide 25% excess oxygen ("excess" has a precise meaning in process analysis: in this case there is 25% more oxygen than the amount needed to completely react with the limiting reactant). the fractional conversion of hbr is 78%.
a) show the degree of freedom analysis. be as specific as possible about labeling the unknowns and completely write out all of the independent equations.
b) calculate the composition (mole fractions) of the product stream.

The mole fractions:

Explanation:

The reaction described is:

The limiting reactant is the HBr (oxygen is in excess).

a) The mass (in moles) balance for this sistem:

(the 0.78 is because of the fractional conversion)

(the 1.25 is because of the oxygen excess)

There is only one degree of freedom in this sistem, you can either deffine the moles of HBr you have or the moles of Br2 you want to produce. The other variables are all linked by the equations above.

b) Base of calculation 100 mol of HBr:

The mole fractions:

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.

50.23 i believe is correct but don't quote me on that.