Explore BrainMass

Determining the reaction direction, initial velocity of reaction and the Haldane relationship in enzyme kinetics.

A reversible reaction described by the chemical equation shown below (equation one) has an equilibrium constant of 10. (S represents substrate, P represents product.) If we have a mixture containing [S]=2x10E-5 M and [P]=3x10E-5M, and we know that KmS=3x10E-5 M, Vmax (forward reaction) =2 micromole /(L min), and Vmax (reverse reaction) = 4 micromole /(L min), answer the following questions.

(a) In which direction will the reaction proceed when the appropriate enzyme is added?
(b) After addition of enzyme, what will the initial velocity be when the reaction starts toward equilibrium?

Equation one:

(refer to the attached file for the equation)


Solution Preview

The TEXT of the solution is presented below. Please refer to the attached file for the full solution, which includes equations.


To answer this question, you will need to have an understanding of chemical reaction kinetics, as well as an understanding of the Haldane relationship between kinetic constants and the equilibrium constant. By combining this information, you will be able to identify in which direction a reaction will proceed upon addition of enzyme, and also calculate the initial velocity for the reaction that occurs once enzyme is added.

The question describes a reversible chemical reaction that is catalyzed by an enzyme. The equilibrium constant (Keq) for any reaction is a ratio of the concentrations of products and reactants. We can write the Keq equation for the reaction given in the question.

For the reaction as ...