Equilibrium help

Oct 2012
1. For a chemical reaction at equilibrium, whihc of the following statements is false?

a) equilibrium can be approached from either side of the reaction
b) The concentration of products and reactant are constant
c) The concentration of products equals the concentration of reactants.
d) The ratio of product concentration to reactant concentration is constant.

I think its A because the rest are true.

2. A homogeneous equilibrium is one where?

a) the products and reactants are all in the same phase.
b) the product and the reactants are not all in the same phase
c) the products and the reactants can only be in the gaseous phase
d) the products and the reactants can only be in an aqueous solution

I think its C or A, not sure.

3. If more reactant is added to a gaseous reaction at equilibrium, what will happen to the value of the equilibrium constant?

a) it will increase
b) it will decrease
c) it will remain the same

I think it is C because only temperature will affect the constant.

4. consider the equilibrium: S8(s) +8O2(g) ---> 8SO2(s)

In which direction will this reaction move if more solid sulfur is added to the reaction vessel?
a) in the forward direction
b) in the reverse direction
c) There will be no change in the position of the equilibrium.

I think it is A

5. If the value of delta G for a reaction is large and positive, then Keq is?
a) very large
b) very small
c) zero
d) equal to 1

I think the answer is a, keq will be very large

6. If the value for Keq is greater than one, then delta G is?

a) positive
b) negative
c) zero
d) equal to 1

I think the answer is a, delta G will be positive


CHF Hall of Fame
May 2010
1. Think about the production of ammonia:

N2 + H2 <===> NH3

You surely did this in class? Do we obtain the same amount of product everytime?

2. You must be sure of your definitions! It's actually A.

3. Correct

4. Correct

5. If delta G is positive, this means the reaction is non spontaneous, meaning the reactants don't easily react.

6. Refer to number 5.