Question

Acetylene burns in air to produce carbon dioxide and water: C2H2(g) + 5/2O2(g) → 2CO2(g) + H2O(l). Use the following thermochemical equations to obtain ΔGr0 at 25 °C for the combustion of acetylene:

C2H2(g) + 3H2(g) → 2CH4(g) ΔGr0 = −310.7 kJ/mol at 25 °C

CH4(g) + 2O2(g) → CO2(g) + 2H2O(l) ΔGr0 = −817.97 kJ/mol at 25 °C

H2(g) + 1/2O2(g) → H2O(l).   ΔGr0 = −237.18 kJ/mol at 25 °C

Answer 1

write the equations and arrange them in a order to get the fianl equation

first reaction remains same

second is multiplied with 2

third reaction is reversed nd multiplied with 3

adding the equations and get final eqation as shown below and calculate the values