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TBR chem- equilibrium

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bajoneswadup

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TBR equilibrium passage 1, #3

According to table 1, the reaction is which of the following?
A: Exothermic
B: Endothermic
C: Adiabatic
D: Isothermal

The table shows increasing pressure upon increasing temp.
The reaction is 2CO2(g) + O2(g) ---> 2CO2(g)
 
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MedPR

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TBR equilibrium passage 1, #3

According to table 1, the reaction is which of the following?
A: Exothermic
B: Endothermic
C: Adiabatic
D: Isothermal

The table shows increasing pressure upon increasing temp.
The reaction is 2CO2(g) + O2(g) ---> 2CO2(g)


Increasing pressure upon increasing temp? Does it not say which way the equilibrium shifts with increasing temp?

Edit: Nevermind, I just looked at it.

That table does not show increasing pressure upon increasing temperature. It shows increasing Kp as the temperature goes up. Kp is the equilibrium constant. If Kp >> 1, the reaction goes to completion. In other words, 0 reactant and all product. Since Kp is increasing as you add heat, that means you are forming more product as you add heat. Lechateliers principle tells us that if you add to one side, equilibrium shifts to the opposite side to maintain balance.

Therefore, the answer is B. Endothermic as written. Endothermic means heat is a reactant, Exothermic means heat is a product.

If it were exothermic as written (answer A), Kp would decrease as Temperature increased.
Answer C is obviously wrong because heat is being gained by the system.
Answer D is obviously wrong because, again, you are not in constant temperature conditions.
 
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