7. In the fume hood: Burn the paper towel.
8. Still in fume hood: Place the beaker over the paper towel.
When the flame goes out, lift the beaker and collect as
much smoke as possible in the bag. Seal the bag.
9. Pour approximately 10 mL of distilled water into the bag,
being careful not to let any of the smoke out. Seal the bag
and swirl the water to mix the smoke particles with the
water.
10. Put 2 drops of pH indicator into the water in the bag,
reseal, and swirl to mix. Record your observations.
11. Clean materials.
12. Answer questions on the back side.
Acid Rain Lab
Name _________________________ Date________
Pre-lab safety:
 Hair tied back? Dangly sleeves, chords, jewelry, etc taken care
of?
 No electronics anywhere in sight. No earbuds, headphones,
cords. NADA.
Safety in the lab:
 Wear goggles or safety glasses at all times
 Pen/pencil and notebook out. Everything else away where it
won’t get tripped over.
 ATTENTIVE, QUIET BEHAVIOR
Materials, per group
Lemon juice, distilled water, bleach, pH indicator, beakers, plastic bags
Liquid
Indicator Color
pH
Number
Acidic, Neutral
or Basic?
Lemon Juice
Water
Procedure:
1. Obtain 3 beakers containing 10 mL of lemon juice, distilled
water, and bleach from the front of the room.
2. Add 2 drops of pH indicator to each beaker and gently
swirl the beakers to mix the solutions.
3. Observe the colors of each solution and record the color
and pH on the chart.
4. Place about 10 mL of distilled water in one of the plastic
bags. Seal the bag and swirl the water around.
5. Add 2 drops of pH indicator to the water in the bag, reseal,
and swirl the water to mix. Record your observations.
6. Place about 10 mL of distilled water into the 2nd plastic
bag. Seal the bag and swirl the water around, then dump
the excess water into the sink.
Bleach
Water only in
plastic bag
Smoke &
Water in
plastic bag
Pre-Lab Questions:
1. Which has a lower pH, an acidic liquid or a basic liquid?
2. Do you think that mixing smoke particles with water will
make the water acidic, basic, or neutral? How will you
observe that?
Post Lab Questions
1. Based on your observations, does the water become acidic,
neutral, or basic when smoke mixes with it?
5. Why are high-elevation forests more severely affected by acidic
deposition than those at lower altitudes?
2. How do your results in this lab compare to what happens to
power plant emissions in the atmosphere?
6. List three ways that acidic deposition could affect the ecosystem
of a lake.
Acidic deposition affects organisms and the environment and its
effects can be far-reaching. Read Basics of Acidic Deposition on
pages 121 to 123 and answer the following questions.
3. How does acid precipitation affect aquatic animals? Describe how
the interdependence of animals and plants in a lake ecosystem
increases the effects of acidic deposition throughout the
ecosystem.
4. How does acidic deposition affect trees and forests? Why does it
inhibit growth? How does it make trees more prone to other
conditions that might kill them?