Question

The balanced equation for the reaction of bromate ion with bromide in acidic solution is given by:

BrO₃⁻ + 5Br⁻ + 6H⁺ ---> 3Br₂ + 3H₂O
At a particular instant in time, the value of Br- t is 3.8 x 10⁻³ mol/L*s. What is the value of delta [Br₂] t in the same units?
A) 6.3 x 10⁻³
B) 1.9 x 10⁻³
C) 3.2 x 10⁻³
D) 2.3 x 10⁻³
E) 3.8 x 10⁻³

Answer 1

The rate of formation of Br₂ is (3/5) * the rate of disappearance of Br⁻. Upon calculating, the value of Δ[Br₂]/δt is found to be 2.3 x 10⁻³ mol/L*s. Hence, the correct answer is Option D) 2.3 x 10⁻³.

Step-by-step explanation:

To determine the rate of appearance of Br₂(aq) at a particular moment during the reaction, we can use the stoichiometry of the balanced equation.

The coefficient of Br₂ in the balanced equation is 3, so for every 3 moles of Br₂ that is formed, 5 moles of Br⁻ are consumed. Therefore, the rate of appearance of Br₂ would be 3 times the rate of disappearance of Br⁻.

Given that the rate of disappearance of Br⁻ at the particular moment is 3.8 x 10⁻³ mol/L*s, the rate of appearance of Br₂ would be 3 times that value, which is 1.14 x 10⁻² mol/L*s.