Yahoo Answers is shutting down on May 4th, 2021 (Eastern Time) and the Yahoo Answers website is now in read-only mode. There will be no changes to other Yahoo properties or services, or your Yahoo account. You can find more information about the Yahoo Answers shutdown and how to download your data on this help page.
Trending News
Use the information below to calculate?
Delta H_2: CH4 (g)+2 O2 (g)--> CO2 (g)+2 H2O (g); delta H= -890kj CH4 (g) +O2 (g)--> CH2O (g)+ H2O (g); Delta H2=? CH2O (g)---> CO2 (g)+H2O (g); delta H3=-518kj
1 Answer
- ?Lv 64 years agoFavorite Answer
Reaction (1) :-
CH₄(g) + 2O₂(g) -----> CO₂(g) + 2H₂O(g) ΔH = -890kJ
ΔH = (ΔHp - ΔHr)
-890kJ = (ΔHf_CO₂ + 2ΔHf_H₂O) - (ΔHf_CH₄ + 2ΔHf_O₂)
ΔHf_O₂(g) = 0
-890kJ = ΔHf_CO₂ + 2ΔHf_H₂O - ΔHf_CH₄ --------(1)
Reaction (3) :-
CH₂O(g) ------> CO₂(g) + H₂O(g) ΔH₃ = -518kJ
-518kJ = ΔHf_CO₂ + ΔHf_H₂O - ΔHf_CH₂O
518kJ = ΔHf_CH₂O - ΔHf_H₂O - ΔHf_CO₂ ------(2)
Reaction (2) :-
CH₄(g) + O₂(g) -----> CH₂O(g) + H₂O(g)
ΔH₂ = ΔHf_CH₂O + ΔHf_H₂O - ΔHf_CH₄ ------(3)
Sum of equations (1) and (2) gives equation (3)
So ΔH₂ = (518kJ) + (-890kJ) = -372kJ
