Chapter 22, Problem 18STP

Interpretation Introduction

Interpretation: The rate of the reaction in terms of moles of product per second needs to be determined.

Concept introduction: The rate of the reaction in terms of product is defined as change in the concentration of product with respect to change in time.

Answer to Problem 18STP

Correct Answer: Option (c) is correct.

Explanation of Solution

Reason for correct option: The given reaction is as follows:

  $A+B\to C$

The initial concentration of A, B and C is 0.35 M, 0.50 M and 0 M respectively. The concentration at time 5 sec is 0.15 M, 0.30 M and 0.40 M respectively.

The rate of the reaction in terms of moles of a product can be determined by taking the difference of the concentration of final and initial concentration of product to the change in time.

  $R=\frac{{\left[C\right]}_f-{\left[C\right]}_i}{t_f-t_i}$

Putting the values,

  $R=\frac{0.40-0}{5-0}=\frac{0.40}{5}=0.08\text{ mol/s}$

Therefore, option (c) is correct.