Chapter 16 Summary

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CHAPTER 16

Acidic Toxins

SUMMARY

KEY TERMS

indicator

pH scale

acid

base

dissociate

strong acid

weak acid

strong base

weak base

dilution

neutralization reaction

titration

equivalence point

Toxins Update

Acids and bases are present in living systems and are a valuable part of the chemistry of life. They are toxic under certain conditions, such as when they are too concentrated or when they upset the pH balance that must be maintained for proper health. The pH number is a measure of the H+ concentration of a solution. The lower the pH, the more acidic a solution is.

There are two main approaches to dealing with toxic acids and bases. One is dilution. This moves the pH toward neutral. Another approach is neutralization. Acids and bases neutralize one another.

REVIEW EXERCISES

Question 16.1

1. What are the main differences between the Arrhenius and Brønsted-Lowry definitions of acids and bases?

Question 16.2

2. Name three substances that you might use to neutralize a hydrochloric acid solution. Write the balanced chemical equation for each reaction.

Question 16.3

3. Explain how a titration procedure works to help you identify the H+ concentration of a sample solution.

Question 16.4

4. Lemon juice has a pH around 2. This is quite acidic and can damage the tissue of the eye.

  1. What is the concentration of hydrogen ions, [H+], in lemon juice?

  2. What is the concentration of hydroxide ions, [OH−]?

Question 16.5

5. Sodium bicarbonate, NaHCO3, is a base.

  1. Explain how sodium bicarbonate can be classified as a base, even though it has no OH− ion.

  2. Explain why you had sodium bicarbonate on hand during the Lab: The Copper Cycle from Unit 1: Alchemy.