Question

Which one of the following will change the value of anequilibrium constant?

a. varying the initial concentration of reactants
b. adding other substances that do not react with any of thespecies involved in the equilibrium
c.varying the initial concentration of products
d. changing temperature
e. changing the volume of the reaction vessel

Answer 1

d. changing temperature

Step-by-step explanation:

The thermodynamic equilibrium constant K is defined as a quantity characterizing the equilibrium of a chemical reaction. For a reaction where concentrations are in equilibrium:

aA + bB ⇄ cC + dD

The equilibrium constant is:

`k = ([C]^c[D]^d)/([A]^a[B]^b)`

Thus, the equilibrium constant will change if:

a. Varying the initial concentration of reactants . FALSE. The k constant doesn't depend of initial concentrations but concentration in equilibrium does.

b. Adding other substances that do not react with any of thespecies involved in the equilibrium . FALSE. The equilibrium constant just depends of substances that are involved in the equilibrium

c. Varying the initial concentration of products . FALSE. Again, equilibrium constant doesn't depend of initial concentrations.

d. Changing temperature . TRUE. As a thermodynamic constant, k depends of temperature thus:

`K = e^(-dG/RT)`

e. Changing the volume of the reaction vessel. FALSE. The changing in the volume of the reaction vessel will change just the initial concentrations of the reactants.

I hope it helps!