Granite, red sandstone, and pea stone will be tested to see which holds up best against acid rain conditions. Samples of each material will be submerged in vinegar to simulate acid rain and their masses measured before and after 24 hours. It is hypothesized granite will deteriorate least since it is most resistant to weathering. The experiment will help recommend the best material for a new statue given the area's acid rain levels.

1. WHAT IS ACID RAIN?WHAT IS ACID RAIN?
• Generally, rain water has a pH value
of 5.6 because of the carbon
dioxide from air dissolved in it.
• Any rainfall has a pH value less
than 5.6 is defined as acid rain.

3. • When gas pollutants e.g. sulphur
dioxide, nitrogen dioxidedissolve
in rain water, various acids are
formed.CO2 + H2O → H2CO3 (carbonic acid)
SO2 + H2O → H2SO3 (sulphorous acid)
NO2 + H2O → HNO2 (nitrous acid) +
HNO3 (nitric acid)

4. CAUSES OF ACID RAINCAUSES OF ACID RAIN
SO2 : 70% NOx : 30%
X = 1 or 2

5. FORMATION OFFORMATION OF
ACID RAINACID RAIN
SO2
NOX
SMOKE FROM
FACTORIES

6. 1.Vegetation1.Vegetation
• Wash away essential nutrients ions
from soil
• Poor growth of plants.
ENVIRONMENTALENVIRONMENTAL
PROBLEMSPROBLEMS

7. 2.Aquatic Life2.Aquatic Life
• Inflow of acidic water containing
poisonous metal ions
• Kill the fish and water plants

8. 3. Building3. Building
• Acid rain attacks the building
materials and causes corrosion.

9. On-line ReferencesOn-line References
• http://igc.apc.org/acidrain/
• http://beakman.com/acid/acid.html
• http://qlink.queensu.ca/~4lrm4/

10. Your TaskYour Task
• Your town council is commissioning a
new statue to be displayed downtown.
You and your lab partner will conduct
an experiment to investigate the effect
of acid rain on various building
materials in order to make a
recommendation to the town council as
to the best material to use for the
statue. In your experiment, vinegar (pH
≈ 3) will simulate acid rain.

11. Research QuestionResearch Question
Of pea stone, red
sandstone, and granite,
which material is the BEST
for building a weather
resistant statute?

12. HypothesisHypothesis
If pea stone, red sandstone, and
granite are subjected to acid rain
(pH ≈ 3) then granite will
deteriorate the least because it is
the most resistant to weathering.

13. Independent VariableIndependent Variable
Type of building
material (pea stone,
red sandstone, and
granite).

14. Dependent VariableDependent Variable
Difference in Remaining Mass
(grams)
(final mass of stone – initial
mass of stone)

15. Control GroupControl Group
Instead of acid rain test
(submerge) the building materials
(pea stone, red sandstone, and
granite) in tap (pure) water with a
pH of ≈ 7.

16. Variables that must be kept
constant
• Same amount of time in the vinegar
(24 hours).
• same amount of vinegar (100 mL),
same mass of building material (20
g).
• same balance.
• same brand of vinegar.
• same size container/lid.

17. Procedure
• Obtain a sample of each rock and record the
mass of the sample in grams on the data table.
• Pour vinegar into each cup until the stone is
completely covered.
• Let the stone sit for 24 hours.
• Pour the vinegar out of each cup and mass the
stone.
• Record the final mass of each type of stone in
the data table.
• Subtract the original mass from the final mass of
each stone and record the data.

18. Data TableData Table
Type of Stone Mass Day 1
(grams)
Mass Day 2
(grams)
Pea stone
Red
Sandstone
Granite