Question

The rate law for thevreaction given velow is k[a][b] if conc of b is increased from 0.1 to 0.3

Answer 1

Question: The rate law for the reaction below is given by the expression k [A][B]

A+B -------> Product

If the concentration of B is increased from 0.1 to 0.3 mole, keeping the value of A at 0.1 mole, the rate constant will be :

(1) k

(2) k/3

(3) 3k

(4) 9k

Solution:

The concentration of a is left unchanged, but the concentration of b is changed to 0.3 mole. When this is done, the rate of the reaction, no doubt, changes, but the rate constant remains the same. Consider the Arrhenius equation, which says:

$k = Ae^{-\frac{-E_{a}}{RT}}$

Which clearly proves that the rate constant does not depend upon the concentration of reactants. So, the rate constant remains same, i.e., k.

Answer 2

Answer:

Question: The rate law for the reaction below is given by the expression k [A][B]

A+B -------> Product

If the concentration of B is increased from 0.1 to 0.3 mole, keeping the value of A at 0.1 mole, the rate constant will be :

(1) k

(2) k/3

(3) 3k

(4) 9k

Solution:

The concentration of a is left unchanged, but the concentration of b is changed to 0.3 mole. When this is done, the rate of the reaction, no doubt, changes, but the rate constant remains the same. Consider the Arrhenius equation, which says:

k = AeE_k=Ae − RT−E a

Which clearly proves that the rate constant does not depend upon the concentration of reactants. So, the rate constant remains same, i.e., k.