State Hess' law of constant heat summation. (b) Calculate the enthalpy of formation of CH4 from the following data:
i) C(s) + O2(g) → CO2(g); ∆H = -393.7 kJ/mol
ii) H2(g) + 1⁄2 O2(g) → H2O(l); ∆H = -285.8 kJ/mol
iii) CH4(g) + 2 O2(g)→ CO2(g) + 2H2O(l); ∆H = -890.4 kJ/mol

-74.6 kj/mol

Explanation:

you can see the answer at the pic

consider the reaction below.

 no rx

at 500 k, the reaction is at equilibrium with the following concentrations.

[pci5]= 0.0095 m

[pci3] = 0.020

[ci2] = 0.020 m

what is the equilibrium constant for the given reaction?

0.042

0.42

2.4

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