Download Testing for Common Gases LAB APPROVED

SNC1D/1P
Name: ____________________________
CHEMICAL IDENTIFICATION TESTS FOR GASES
Learning Goal:
At the end of this experiment, I will be able to use standard tests to identify 3 common unknown gases.
Purpose:
To identify the gas produced during three chemical reactions
Materials:
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safety goggles
piece of zinc magnesium ribbon
1.0 mol/L hydrochloric acid
sodium bicarbonate
vinegar
scoopula
limewater
3% hydrogen peroxide
yeast
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10 mL graduated cylinder
Forceps (tweezers)
distilled water
4 clean test tubes
rubber stopper
test tube rack
wooden splints
Bunsen burner
matches/flint sparker
Safety Precautions:
● Put on splash-proof goggles and lab apron before beginning the lab.
● Hydrochloric acid and hydrogen peroxide are corrosive.
● Wash hands after completing the lab.
Procedures: (5 marks for safety, procedure and clean-up)
Part 1: Reaction of Hydrogen Peroxide and Yeast
1. Measure 10 mL of 3% hydrogen peroxide in the 10 mL
graduated cylinder. Slowly pour the hydrogen
peroxide into the test tube. Record a description of
the hydrogen peroxide in your observation table.
2. Cover the tip of a scoopula with a pencil eraser sized
amount of yeast. Record a description of the yeast in
your observation table. Add the yeast into the test
tube containing the hydrogen peroxide. Plug the test
tube with a rubber stopper. Record your observations
of the chemical reaction in your data table.
3. Light a wooden splint with the Bunsen burner, then
blow out its flame. Insert the glowing splint (fig. 1)
halfway into test tube. Record your observations in
your observation table.
4. Dispose of the contents into the waste container.
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SNC1D/1P
Name: ____________________________
Part 2: Reaction of Zinc and Hydrochloric Acid
1. Measure 5.0 mL of 1.0 mol/L hydrochloric acid in
a 10 mL graduated cylinder. Slowly pour the
hydrochloric acid into the test tube. Record a
description of the hydrochloric acid in your
observation table.
2. Using forceps place a piece of zinc on a dry
watch glass. Record a description of the zinc in
your observation table.
3. Using forceps, carefully add the zinc into the test
tube containing the hydrochloric acid. Plug the
test tube using the rubber stopper. Record your
observations in your observation table.
4. Light a wooden splint with the Bunsen burner
and bring the still burning splint (fig. 2) to the
mouth of the test tube. Record your
observations in your data table.
5. Dispose of the contents of your test tube into the
waste container.
Part 2: Reaction of Sodium Bicarbonate and Vinegar
1. Set up two test tubes in the test tube rack. Measure 5.0 mL of vinegar in a 10
mL graduated cylinder. Slowly pour the vinegar into one of the test tubes.
Record a description of the vinegar in your observation table.
2. Measure 5.0 mL of limewater in a 10 mL graduated cylinder. Record a
description of the limewater in your observation table.
3. Cover the tip of a scoopula with about a pencil eraser amount of sodium
hydrogen carbonate. Record a description of the solid in your observation table.
4. Add the sodium hydrogen carbonate into the test tube containing the vinegar.
Record your observations.
5. When the bubbling stops slowly pour the gas produced into the test tube
containing the limewater. Stopper the test tube containing the limewater and
shake the contents gently. Record your observations in your observation table.
6. Dispose of the contents of the test tube into the waste container.
Analysis & Extension:
1. Using your table of observations, identify each gas produced in the reactions.
Explain your reasoning for choosing each gas. Hint: characteristic properties! (3)
2. In each part of the activity, were the changes physical changes or chemical
changes? Provide reasons for your answers. (2)
3. From your observations in this activity, suggest reasons why
a) Birthday balloons are filled with helium, not hydrogen. (1)
b) During surgery using oxygen cylinders, medical staff wear coverings
over their shoes to eliminate sparks produced by static electricity. (1)
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SNC1D/1P
Name: ____________________________
COMPLETE AND SUBMIT ONLY THIS PORTION OF THE LAB FOR MARKS.
Observations: (3)
Reactants
Description of
reactants
Description
of product
Burning
splint test
Glowing
splint test
Limewater
test
Zinc and
Hydrochloric Acid
Sodium Hydrogen
Carbonate and
Vinegar
Hydrogen
peroxide and
yeast
Properties of some common lab gases at room temperature:
Oxygen:
Hydrogen:
Carbon Dioxide:
Water Vapour:
Methane:
colourless, odourless, tasteless gas, it is highly reactive and a strong
oxidizer.
colourless, odourless, tasteless gas, it is highly flammable and explosive.
colourless, odourless, tasteless gas, it is not very reactive and
extinguishes flames.
colourless, odourless, tasteless gas, mildly reactive, condenses easily on
cool objects.
colourless, odourless (naturally), tasteless gas, highly flammable – an
odourant is added when used in homes and industry for safety.
Analysis & Extension:
Answer the analysis and extension questions on the back. Title & number your responses.
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