C2H2(g) + 2 H2(g)--> C2H6(g)
Information about the substances involved in the reaction represented above is summarized in the following tables.
Substance/ So (J/mol∙K) /∆Hºf (kJ/mol)
C2H2(g) / 200.9 / 226.7
H2(g) / 130.7 / 0
C2H6(g)/ ?? / -84.7
Bond Bond Energy (kJ/mol)
C-C 347
C=C 611
C-H 414
H-H 436
1.If the value of the standard entropy change, ∆Sº for the reaction is -232.7 joules per mole∙Kelvin, calculate the standard molar entropy, Sº, of C2H6 gas.
2.Calculate the value of the standard free-energy change, ∆Gº, for the
reaction. What does the sign of ∆Gº indicate about the reaction above?
3.Calculate the value of the equilibrium constant for the reaction at 298 K.
4.Calculate the value of the C C(triple bond) bond energy in C2H2 in kJ/mole.
C C= [ C triple bond C]