# Rxn Equilibrium help

#### allstardentist

##### All-Star
10+ Year Member
NO + 1/2 O2 <-> NO2

What would be the effect upon the equilibrium if the size of the vessel decreased?
A. The eq. would shift to the right
B. The eq. would shift to the left
C. The eq. would not change
D. Keq would increase
E. Two of the above.

The answer is A. I thought it was E (thinking A and D are correct). I was thinking if there are more moles of the product, then the Keq increases. Can someone please tell me what is wrong with my logic?. Thanks

#### fancymylotus

##### A Whole New World
15+ Year Member
allstardentist said:
NO + 1/2 O2 <-> NO2

What would be the effect upon the equilibrium if the size of the vessel decreased?
A. The eq. would shift to the right
B. The eq. would shift to the left
C. The eq. would not change
D. Keq would increase
E. Two of the above.

The answer is A. I thought it was E (thinking A and D are correct). I was thinking if there are more moles of the product, then the Keq increases. Can someone please tell me what is wrong with my logic?. Thanks

i *think* that if you decrease vessel size, that means youre increasing pressure,with increased pressure,eq shifts towards the side with less moles. which would be the right. im pretty sure im right..someone will correct me if im not.

#### tom_servo_dds

##### Senior Member
10+ Year Member
amsie said:
i *think* that if you decrease vessel size, that means youre increasing pressure,with increased pressure,eq shifts towards the side with less moles. which would be the right. im pretty sure im right..someone will correct me if im not.

You are absolutely right on this one amsie! And I think your dog is WAY cute One way that I like to think of these is to visualize how many molecules per volume of space the container has (as a ratio). That way, if I'm going from a larger container to a smaller one, I know the moles have to decrease. This is in keeping with LaChatlie's principle.

#### fancymylotus

##### A Whole New World
15+ Year Member
tom_servo_dds said:
You are absolutely right on this one amsie! And I think your dog is WAY cute One way that I like to think of these is to visualize how many molecules per volume of space the container has (as a ratio). That way, if I'm going from a larger container to a smaller one, I know the moles have to decrease. This is in keeping with LaChatlie's principle.

thanks shes quite the princess. there are many ways to word lechateliers principle problems,i guess their way of trying to **** with your brain. BAH!