Chapter 7, Problem 25A

Interpretation Introduction

Interpretation:

The unbalanced chemical equation corresponding to the formation of ozone gas from oxygen gas needs to be presented.

Concept Introduction:

• A chemical reaction is expressed as a chemical equation having reactants and products on left and right side of the reaction arrow respectively.

  $\text{Reactants }\to \text{ Products}$

• It also gives the physical state (solid (s), liquid (l), gas (g) and the amount of reactants and products involved in the reaction.

Answer to Problem 25A

  ${\text{O}}_2\text{(g) }\stackrel{\text{UV light}}{\to }\text{ O + O}$

  ${\text{O}}_2\text{(g) + O }\to {\text{ O}}_3\text{(g)}$

Explanation of Solution

The given process involves the formation of ozone gas from oxygen gas. This takes place in two steps:

Step 1: Oxygen gas in the presence of UV light breaks into oxygen atoms.

Unbalanced equation:

  ${\text{O}}_2\text{(g) }\stackrel{\text{UV light}}{\to }\text{ O + O}$

Step 2: Oxygen atoms combine with oxygen gas to form ozone.

Unbalanced equation:

  ${\text{O}}_2\text{(g) + O }\to {\text{ O}}_3\text{(g)}$

Conclusion

Therefore ozone is formed via a 2 step process in which first the oxygen gas splits into atoms which in turn combine with a molecule of oxygen to form the required product.