spacer Introduction
>Home Page 
>About this Guide 
>Table of Contents

1.  What you can do
2.  Water
3.  Ecology
4.  Amphibians
5.  Environmental Issues
6.  Keystone species
7.  Get Wet!-
     Field Study Ideas

8.  The Zoo Experience
9.  Frogs & Friends
10. Case Studies
11. Resources
12. Glossary

Wetland Curriculum Resource
Unit 5. Environmental Issues -

(Level: 4 : 7 : 10 acad : 10 appl
:: Acid Deposition)

Purpose: To observe the effects of an acid solution on plant growth.

What You Need: 5 plastic pots :: distilled water :: potting soil :: vinegar :: 15 bean seeds :: pH test kit :: permanent marker :: 5 1-litre containers :: graduated cylinder

What You Do:

  1. Prepare the following 1 litre solutions:
    Pot 1 - 1 litre of vinegar
    Pot 2 - 750 ml vinegar + 250 ml distilled water
    Pot 3 - 500 ml vinegar + 500 ml distilled water
    Pot 4 - 250 ml vinegar + 750 ml distilled water
    Pot 5 - 1 litre of distilled water
  2. Measure and record the pH of each of the solutions.
  3. Number the 5 plastic pots consecutively.
  4. Fill each pot with equal amounts of potting soil and plant 3 beans in each pot. Place in an area where all pots receive the same amount of bright light and temperature.
  5. Water the 5 pots each day with 50 ml of solution each time. Ensure that the correct solution goes in the corresponding pot each time.
  6. Observe and record the growth of the beans over a 3-4 week period.


  1. From your observations, what effects do the varying amounts of acidity have on plant development?
  2. What can you conclude about the importance of pH in the growth of plants?
  3. Soils in a bog are very acidic and lack nutrients, specifically nitrogen. How is the pitcher plant adapted to obtain nitrogen while growing in a bog?
  4. Why are the soils in northern Ontario much more susceptible to the effects of acid rain than the soils in southern Ontario?
  5. How do acidic soils affect amphibians?

The following chart lists four pH indicators and the colour changes that occur during testing.


Colour In Acid

Colour In Base

Litmus paper






Methyl Orange



Bromthymol Blue



Click here to go back to the list of activities for this unit.


Copyright 2013 Adopt-A-Pond - Toronto Zoo       All Rights Reserved