Equal mases of ethane and hydrogen are mixed in an empty container at 25 degree celcius. The fraction of the total pressure exerted by hydrogen is

15/16

Explanation:

We need to find the number of moles of hydrogen and number of moles of ethane present.

Since we have the same mass, m for both substances, the number of moles of hydrogen, n = m/M where M = molar mass of hydrogen molecule

Since hydrogen is H₂, M = 2 × 1 g/mol = 2 × 1 g/mol = 2 mol.

n = m/M

n = m/2

Also, number of moles of ethane, n' = m/M' where M' = molar mass of ethane.

Since ethane is C₂H₆, M' = 2 × 12 g/mol + 6 × 1 g/mol = 24 g/mol + 6 g/mol = 30 g/mol

n' = m/M'

n' = m/30

The total number of moles of gas present is thus n" = n + n' = m/2 + m/30 = (15m + m)/30 = 16m/30

The mole fraction of hydrogen is thus number of moles of hydrogen/total number of moles = n/n" = m/2 ÷ 16m/30 = m/2 × 30/16m = 15/16

Also, since the partial pressure due to hydrogen, P = mole fraction × total pressure, P'

P/P' = mole fraction = 15/16

So, The fraction of the total pressure exerted by hydrogen is 15/16

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.