Question

A plot of 1/[BrO-] vs. time is linear and the slope is equal to 0.056 M-1s-1. If the initial concentration of BrO- is 0.65 M, how long will it take one-half of the BrO- ion to react

Answer 1

Answer:

time taken for one-half of the BrO⁻ ion to react is t= 27.45 secs

Explanation:

equation of reaction

3BrO⁻(aq) → BrO₃⁻(aq) + 2Br⁻(aq) (second order reaction)

given

the slope of the graph is 0.056M⁻¹s⁻¹ = k(constant)

initial concentration [A]₀ = 0.65M

for second order reaction,we can calculate the time taken for one-half of the BrO- ion to react using:

$\frac{1}{[A]}$ =$\frac{1}{[A]}$₀ ⁺ k × t

where initial concentration [A]₀ = 0.65M

[A] = [A]₀÷2 = 0.325M

$\frac{1}{0.325M}$ = $\frac{1}{0.65M}$ + 0.056M⁻¹s⁻¹ × t

3.077= 1.54 + 0.056t

3.077-1.54=0.056t

1.537=0.056t

t= 27.45 secs