# Equilibrium constant

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#### sizillyd

##### Go Pack
10+ Year Member
Which of the following will increase the value of the equilibrium constant for the following reaction?

CaCO3(s) <-> CaO(s) + CO2(g) Change in H=178 kJ

B) Removing CO2
C) Increasing Temperature
D) Decreasing temperature

Is my logic accurate here: The only thing that can change the equilibrium constant is temperature

So that eliminates A and B

Now we make the Keq equation.
Keq=[CO2] because it is the only gaseous or aqueous substance present.

We then see that change in H is positive. So it is an endothermic rxn and heat can be a reactant. Therefore if you increase temperature, the equation will shift to the right increasing amount of CO2, changing the Keq.

Is this right? Just looking for some insight. Thanks a lot.

#### Cool Beans

##### Full Member
10+ Year Member
You nailed it! Perfect!

#### PiBond

##### Call me Bond...PiBond
10+ Year Member
Which of the following will increase the value of the equilibrium constant for the following reaction?

CaCO3(s) <-> CaO(s) + CO2(g) Change in H=178 kJ

B) Removing CO2
C) Increasing Temperature
D) Decreasing temperature

Is my logic accurate here: The only thing that can change the equilibrium constant is temperature

So that eliminates A and B

Now we make the Keq equation.
Keq=[CO2] because it is the only gaseous or aqueous substance present.

We then see that change in H is positive. So it is an endothermic rxn and heat can be a reactant. Therefore if you increase temperature, the equation will shift to the right increasing amount of CO2, changing the Keq.

Is this right? Just looking for some insight. Thanks a lot.

you're thinking of it in more of a Le chatlier way. increasing temp changes your equilibrium constant as shown by the arrhenius equation

#### Phantastic

##### Full Member
10+ Year Member
15+ Year Member
you're thinking of it in more of a Le chatlier way. increasing temp changes your equilibrium constant as shown by the arrhenius equation

Careful! Don't confuse kinetics and thermodynamics. The Arrhenius equation speaks of the effects of temperature on the rate constant. Increasing T will always increase the rate, and decreasing T will always decrease the rate.

Whether or not an increase in T will increase the product concentration depends on the enthalpy of the reaction, a thermodynamic quantity. This is one situation where temperature can be considered a thermodynamic consideration.