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Postby dtolentino1E » Sun Feb 16, 2020 2:16 pm

A reaction used in the production of gaseous fuels from coal, which is mainly carbon, is C(s) + H2O(g) <--> CO(g) + H2(g). (a) Evaluate K At 900 K, given that the standard Gibbs free energies of formation of CO(g) and H2O(g) at 900 K are 2191.28 kJ/mol and 2198.08 kJ/mol, respectively. (b) A sample of graphite of mass 5.20 kg and 125 g of water were placed into a 10.0-L container and heated to 900 K. What are the equilibrium concentrations?

for part b), the solutions manual excludes C(s) in the final equilibrium concentrations. why??

Elena Bell 1C
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Re: 5.55

Postby Elena Bell 1C » Sun Feb 16, 2020 2:29 pm

Since C(s) is in solid form, it is not included in the equation for the equilibrium constant. There is no concentration for C(s) at equilibrium because it does not change much from the initial concentration and is not related to equilibrium.

Sofia Barker 2C
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Re: 5.55

Postby Sofia Barker 2C » Sun Feb 16, 2020 3:37 pm

C(s) is irrelevant because it is in solid form. The concentrations of solids do not change throughout a reaction, which is why solids are considered pure substances.

Megan Vu 1J
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Re: 5.55

Postby Megan Vu 1J » Wed Feb 19, 2020 1:03 pm

C is not included because it is a solid. Since it is a solid, it is not able to be included in the chemical equation for ICE because we do not include solids or liquids.

You should only include aqueous solutions or gases, and then, you are able to find the equilibrium concentrations for the question.

Posts: 104
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Re: 5.55

Postby AKhanna_3H » Wed Feb 19, 2020 1:06 pm

Solids and liquids are not included in equilibrium constants. Only gases and aqueous solutions are included.

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