Module 5 Intro

Module 5—Acids and Bases

Reflect and Connect

At the beginning of this lesson, you learned that indigenous North American people were able to survive very well on a corn-based diet, whereas other cultures did not fare so well. Pellagra is a condition caused by a lack of niacin in the diet. The symptoms of pellagra include “the four D's”—diarrhea, dermatitis, dementia, and death. Niacin, also known as vitamin B3, is critical to cellular metabolism and DNA repair.

When the indigenous North American people prepared their corn for foods, they soaked and cooked the corn in limewater—a basic solution that removes the outer hull of the corn. By removing the hull, the corn could be ground much more effectively, dramatically improving the availability of vitamins and minerals, like niacin, within the corn. Since other cultures did not prepare the corn by soaking it in a basic solution to remove the hull, the foods they ate that were based on corn lacked the necessary nutrients to support their health.

Reflect on the Big Picture

Kitchen Chemistry Project—Using Acids and Bases in Cooking

The use of the basic solution, limewater, to prepare corn is one example of how acids and bases can be used in the preparation of foods. How are acids or bases used in the preparation of the foods you consume?

Find a copy of your favourite recipe, or read the label of something you have eaten recently.

Review the list of ingredients; then do the following:

• Identify at least one acidic or basic substance in the list of ingredients.
  
  

• Write the common name, IUPAC name, and the chemical formula for this substance.
  
  

• Using a relevant chemical reaction, explain why this substance is used and why the acidic or basic properties of this substance are necessary.

Discuss

Post a copy of your project to the discussion board, and review the work of as many other students as possible. Save a copy of your project to your course folder. You will receive further information from your teacher if your teacher wants you to submit your project for assessment purposes.