Chapter 14, Problem 87UTC

The chapter sections to review are shown in parentheses at the end of each problem.
14.87 Determine if each of the following diagrams represents a strong acid or a weak acid. The acid has the formula HX. (14.3)

Interpretation Introduction

Interpretation:

To identify the strong and weak acids, given the diagrams with the ion species.

  

Concept introduction:

• Weak acids will not dissociate completely
• Strong acid will dissociate 100% in solution.

To determine: The weak and strong acids

Answer to Problem 87UTC

Solution: weak acid is A; strong acid is B

Explanation of Solution

An acid is said to be a strong acid if it will be 100% dissociated into ions in the solution. The acid will donate all of its acidic protons, and therefore, will have a higher hydronium ion concentration in solution after dissolution. The pH is likely to be lower.

An acid is said to be a weak acid if it will NOT be 100% dissociated into ions in the solution. The acid will not donate all its acidic protons, and therefore, will form equilibrium between ions and acid. The pH is likely to be higher.

Since, the number of ions ( ${\text{H}}_{\text{3}}{\text{O}}^{+}$ and ${\text{X}}^{-}$ ) are more in beaker B thus, it represents a strong acid.

Conclusion

Weak acids and strong acids can be identified if the dissociation factor is given.