Question

Calculate the rate of the reaction A B C D + → +​

Answer 1

Answer:

0/[A][B][C][D]

Explanation:

Kc=Rf/Rb

Answer 2

The rate of the reaction A+ B ---> C +  D

Explanation:

Law of mass action

It states that: Rate of a reaction is directly proportional to concentration of reactants raised to their respective moles.

Consider a reaction: aA + bB--->  cC + dD

According to this law:

Rate of forward reaction depends upon(directly proportional ) the concentration of reactants raised to their respective moles that is :

  Or, R =K[A]a[B]b

Where ‘K’ is rate constant or velocity constant. We can attain equilibrium from both sides:

For forward reaction:

Rf =Kf[A]a[B]b

Where Rf and Kf is rate for forward and constant for forward reaction .

Therefore,

 For backward reaction:

 Rb = Kb [C]c[D]d

At equilibrium: Rate of forward reaction = rate of backward reaction

That is: Kf[A]a[B]b = Kb[C]c[D]d

But, Kc=Kf/Kb (where Kc is equilibrium constant)

Hence ,

Kc = [A]a[B]b/[C]c[D]d