Learning Goal: To understand the relationship between the equilibrium constant a

Question

Learning Goal:

To understand the relationship between the equilibrium constant and rate constants.

For a general chemical equation

A+B?C+D

the equilibrium constant can be expressed as a ratio of the concentrations:

Kc=[C][D][A][B]

If this is an elementary chemical reaction, then there is a single forward rate and a single reverse rate for this reaction, which can be written as follows:

forward ratereverse rate==kf[A][B]kr[C][D]

where kf and kr are the forward and reverse rate constants, respectively. When equilibrium is reached, the forward and reverse rates are equal:

kf[A][B]=kr[C][D]

Thus, the rate constants are related to the equilibrium constant in the following manner:

Kc=kfkr=[C][D][A][B]

Part A

For a certain reaction, Kc = 7.37

Explanation / Answer

Kc = Kf/Kr

A) Kc= 7.37*10^-3

Kf = 1.87*10^-3 M-2 S-1

Kr = Kf /Kc = 17/67 = 0.253 M-2 S-1

B) after adding catalyst also there will be no change in Kc

Kr = Kf / Kc = 1.96*10^5 / 1.20*10^4 = 16.33 S-1

C) for an exothermic reaction

Kc decreases as temperature is increased in accordance with Le chatlier's principle

Related Questions

Navigate

• Browse (All)
• Browse L
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.