Chapter 1.2, Problem 1RQ

Interpretation Introduction

Interpretation : The relationship between chemistry homework and final grading needs to be explained using an example of an experiment in the chemistry.

Concept Introduction :

A complete process can be thought of as the summation of many small processes.

Explanation of Solution

Carbon dioxide is produced in two different ways namely by burning carbon completely or burning carbon partially followed by burning of CO. Heat energy is the same in both the processes.

Carbon dioxide is produced in two different processes as shown below.

  $\begin{array}{c}{\text{C(s)+O}}_{\text{2}}\text{(g)}\to {\text{CO}}_{\text{2}}\text{(g)}\mathrm{.......}\text{(1) }\Delta \text{H=-x kJ/mol}\\ \text{C(s)+}\frac{1}{2}{\text{O}}_{\text{2}}\text{(g)}\to \text{CO(g)}\mathrm{.......}\text{(2) }\Delta \text{H=-y kJ/mol}\\ \text{CO(g)+}\frac{1}{2}{\text{O}}_{\text{2}}\text{(g)}\to {\text{CO}}_{\text{2}}\text{(g)}\mathrm{.......}\text{(3) }\Delta \text{H=-z kJ/mol}\\ \text{x=y+z}\text{.}\end{array}$

From the above equation, it is clear that heat energy released is the same in single and multistep processes.

This is similar to get a final grade in a course by doing chemistry homework as there is a contribution of all the homework in the determination of the final grade of the course.

Conclusion

Production of CO₂ in two different paths is shown as an experiment to show the relationship between doing chemistry homework and getting a final grade in the course.