Question

A reaction is second order with respect to a reactant. How is the rate affected if the concentration is reduced to half? What is the unit of rate constant

Answer 1

In physical and analytical chemistry, colorimetry or colourimetry is a technique "used to determine the ... Only after the device has been calibrated can you use it to find the densities and/or concentrations ... A similar colorimetric assay, the Bicinchoninic acid assay, uses a chemical reaction to determine protein concentration.

Answer 2

Hey !!

Consider the reaction nR -------> Products

As the reaction is of second order

             Rate, r = k [R]² -------> (1)

If the concentration of the reactants reduced to half, then

         Rate, r' = k[R/2]² -----------> (2)

Dividing equation (2) by (1), we get

                r'/r = k[R]² / 4k [R]² = 1/4

                r' = 1/4r , rate of reaction becomes 1/4th of the initial state.

Therefore, the unit of rate constant is mol⁻¹L s⁻¹

Hope it helps you !!