Why is This Reaction Endothermic?

[Nanu Nana]

Homework Statement

At 1500 ° C , CO is formed more than at 1000 ° C. Is the reaction from left to right exothermic or endothermic?

Homework Equations

C(s) + H₂O ↔CO(g) + H2[/B]

The Attempt at a Solution

I think its Exothermic reaction . The temperature is increased from 1000°C to 1500 °C . If heat increases the CO + H2 (products) shall produced more. Heat is a product in a exothermic reaction .So
C(s) + H2 ↔CO(g) + H2 +x KJ
But correct answer seems to be endothermic. I don't know why?[/B]

 

[Ygggdrasil]

If the system is initially at equilibrium then you add more water vapor, in which direction do you expect the reaction to go? Similarly, if the system is initially at equilibrium then you add more hydrogen gas, in which direction do you expect the reaction to go?

 

[Nanu Nana]

If you add hydrogen , the reaction shifts to the right

 

[Ygggdrasil]

So if you add more hydrogen, the system will react by making even more hydrogen? You should review Le Chatalier's principle:
http://chemwiki.ucdavis.edu/Core/Physical_Chemistry/Equilibria/Le_Chatelier's_Principle
https://www.khanacademy.org/science...emical-equilibrium/v/le-chatelier-s-principle

Bascially, adding hydrogen moves the system out of equilibrium. In order to restore equilibrium, would the system need to make more product or make more reactant?

 

[Jen1114]

If the products increase when the temperature is increased, then the reaction has to be endothermic. The energy could then be looked at as a reactant and when you increase the reactants, the system has to shift to making more product to compensate- therefore the system would create more CO at higher temperatures.

 

[NihalRi]

In an equilibrium reaction the system always tries to counter the change introduced. In this reaction the temperature increases so the system tries to decrease the temperature by increasing the production of CO. So the forward reaction decreases the surrounding temperature meaning it is an endothermic reaction.