Module 5 Intro

1. Module 5 Intro

Introduction

Module 5—Acids and Bases

Module Introduction

Recall from previous science courses that acids taste sour. The sour “kick” of many foods people eat is due to acids—often listed as ingredients. You may also recall your teacher cautioning you in the laboratory that acids can damage your skin. Knowing this, have you ever wondered why some acids can be used in foods? Does the concentration of an acid influence its properties? Do other factors influence the observable characteristics of acids? How can two acidic solutions with equal solute concentrations have different pH values?

In this module you will learn the answers to these questions and explore several aspects of acid-base chemistry.

In Lesson 2, there are theories, like Arrhenius’s theory, that attempt to explain and predict the behaviour of acidic and basic substances when they are dissolved in an aqueous solution. However, you may have found situations where this theory was not adequate when explaining and predicting your observations of the behaviour of an acid or base. In this module you will learn why and in what way the Arrhenius theory had to be modified to overcome these limitations.

Scientific theories are human inventions used to explain events that occur in nature and predict future results. While learning acid-base chemistry, you will pay more attention to different theories. What are the limitations of the different theories you will use?
How do significant digits communicate the appropriate information about acidic and basic solutions?