Question

For a first order reaction , `A to` Products, the concentrations of A changes from 0.1 M to 0.025 M in 40 minutes. The rate of reaction when the concentration of A is 0.01 M is:
A. `1.73xx10^(-5) m//min`
B. `3.47xx10^(-4)M//min`
C. `3.47xx10^(-5) M/min `
D. `1.83 xx10^(-4) M//min`

Answer 1

Correct Answer - B
`k=(2.303)/(40)log""(0.1)/(0.025)`
`k=(0.693)/(20)`
For a F.O.R rate `=K [A],`
rate `=(0.693)/(20)xx10^(-2)=3.47xx10^(-4)M//min.`