Acid Rain: Should We Be Concerned?

2.8 based on 5 ratings

Updated on Mar 15, 2013

Type

Physical Science, Earth Science

6-8

Medium

Steel wool pads: $5, Vinegar: $2, Lemon Juice: $2

None

Up to 1 week

In this experiment we will be examining oxidation and acid rain. We will establish the effects of pH on corrosion of different metals and assess the acidity of our local rainwater.

  • Coarse steel wool pads - without soap. Available at superstores or hardware stores.
  • Lemon Juice
  • Vinegar
  • 4 - 250mL glass beakers or glass bowls or glass jars
  • pH paper, or meter

In recent years the effects of industrial waste products such as ozone depletion, global warming, and acid rain, have gained much attention. Rain itself is normally acidic but byproducts of burning fossil fuels react with the air and rain decreasing the pH or amount of hydrogen atoms. Chemical reactions are dependent on pH, most notably in metals. Rust occurs when metal comes into contact with water and oxygen known as oxidation. This reaction has important implications on metal structures, such as bridges. When it rains the rainwater reacts with air and metal structures leading to rust and corrosion. In this experiment we will be examining the oxidation of steel wool using tap water, local rainwater, vinegar, and lemon juice and determine the potential hazards of acid rain.

  • pH
  • Oxidation
  • Corrosion

  • How does pH affect the corrosion rate of different metals?
  • What is the pH of local rainwater and how does this affect us?

  1. Collect rainwater. You may have to put this experiment on hold until you can collect local rainwater (check your local weather). Place a glass jar outside while it rains and collect 2-4 cups of rainwater.
  2. Test the pH of the tap water, rainwater, vinegar, and lemon juice using pH paper or a meter. Record the pH.
  3. Cut 4 pieces of steel wool approximately 2" x 2".
  4. Place a piece of steel wool into each beaker.
  5. Fill each beaker and label with the following:
    1. Tap water
    2. Rainwater
    3. Vinegar
    4. Lemon Juice
  6. Leave the beakers uncovered and exposed to air overnight.
  7. On day 2 examine each piece of wool and record your observations:
    1. Is there rust?
    2. How much rust? 25%, 50%, 75%
  8. Place your results on a chart. You can also include photographs of the steel wool.
Tap Water
Rainwater
Vinegar
Lemon Juice
pH
7.4
5.2
3.1
2.3
Corrosion
25%
50%
75%
90%
  1. Graph your results: pH vs. percent of rust.

Bibliography

Melissa Bautista is a research scientist, freelance editor, and writer, with a focus in Neuroscience. She believes in establishing solid foundations in education through experience, creativity, and collaboration. She is fascinated by pedagogy and the concept of learning through living.

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