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THE PROPERTIES OF OXYGEN AND CARBON
DIOXIDE
CHAPTER 5: CHAPTER 5: THE AIR AROUND US THE AIR AROUND US
ACTIVITY 5.4 Activities Observation and inferences
Oxygen Carbon dioxide
A. Solubility in water
1. Invert a test tube full of oxygen into a beaker of water as shown in the diagram.
2. Do the same with a test tube of carbon dioxide.
3. Record your observations.
Level of water rises a little in the test tube.
Level of water rises a little in the test tube.
Gas
Water
Activities Observation and inferences
Oxygen Carbon dioxide
B. Solubility in sodium hydroxide
1.Invert a test tube full of oxygen into a beaker of sodium hydroxide as shown in the diagram.2.Do the same with a test tube of carbon dioxide.3.Record your observations.
Sodium hydroxide solution does not rises in the test tube.
Oxygen is not soluble in sodium hydroxide solution.
Sodium hydroxide solution rises to fill up the test tube.
Carbon dioxide is soluble in sodium hydroxide solution.
Gas
Sodium hydroxid
e
Activities Observation and inferences
Oxygen Carbon dioxide
C. Testing with a burning wooden splinter
1.Insert a burning wooden splinter into a test tube of oxygen. 2.Do the same with a test tube of carbon dioxide.3.Observe what happen to the burning wooden splinter.
Wooden splinter continues to burn.
Oxygen supports combustion but does not burn
Flame of wooden splinter goes out.
Carbon dioxide does not support combustion and does not burn.
Gas
Burning
wooden
splinter
Activities Observation and inferences
Oxygen Carbon dioxide
D. Testing with a glowing wooden splinter
1.Insert a glowing wooden splinter into a test tube of oxygen. 2.Do the same with a test tube of carbon dioxide.3.Observe what happen to the glowing wooden splinter.
The glowing wooden splinter ignites.
Oxygen supports combustion but does not burn
The glowing wooden splinter goes out.
Carbon dioxide does not support combustion and does not burn.
Gas
Glowing
wooden
splinter
Activities Observation and inferences
Oxygen Carbon dioxide
E. Testing with litmus paper.
1.Open the rubber stopper of test tube containing oxygen and insert red litmus paper and blue litmus paper.2.Close the test tube with the stopper.3.Record any change to the litmus paper.4.Do the same with the test tube containing carbon dioxide.
No change in colours of the litmus paper.
Oxygen is neutral.
The moist blue litmus paper turns red
Carbon dioxide is acidic.
Gas
Red litmu
s pape
r
Blue litmu
s pape
r
Activities Observation and inferences
Oxygen Carbon dioxide
F. Testing with limewater.
1.Open the rubber stopper of test tube containing oxygen and add a few drops containing limewater. 2.Close the test tube with the stopper and shake it.3.Record any change to the colour of limewater.4.Do the same with the test tube containing carbon dioxide.
The limewater remains clear.
Oxygen does not react with limewater.
The limewater turns cloudy.
Carbon dioxide reacts with limewater to form insoluble calcium carbonate which look cloudy.
limewater
Gas
Activities Observation and inferences
Oxygen Carbon dioxide
G. Testing with bicarbonate indicator.
1.Open the rubber stopper of test tube containing oxygen and add a few drops containing bicarbonate indicator. 2.Close the test tube with the stopper and shake it.3.Record any change to the colour of bicarbonate indicator.4.Do the same with the test tube containing carbon dioxide.
The colour of the bicarbonate indicator remains red.
Oxygen is neutral.
The colour of the bicarbonate indicator changed from red to yellow. .Carbon dioxide is acidic.
Gas
Bicarbonate
indicator
Comparison between oxygen and carbon dioxide
Properties Oxygen Carbon dioxide
Solubility in water
Solubility in sodium hydroxide solution
Effect on a burning wooden splinter
Effect on a glowing wooden splinter
Effect on red and blue litmus paper
Effect on limewater
Effect on bicarbonate indicator
Slightly soluble Slightly soluble
Very soluble
Splinter burns more brightly.
Limewater turns cloudy
Changes the colour of indicator from
red to yellowNo changes
Not soluble
Splinter goes out
Splinter is ignited Splinter goes out
No changes. Oxygen is neutral
Changes the moist blue litmus paper
to red.
No changes
Test for oxygen and carbon dioxide Test
1. Test for oxygen a) the presence of oxygen can
be test with a glowing splinter.
b) When a glowing splinter is put into a test tube containing oxygen, it will light up.
c) This is because oxygen support combustion.
2. Test for carbon dioxidea) the presence of carbon dioxide can be test with limewater.b)Limewater becomes cloudy in the presence of carbon dioxide c) This is because carbon dioxide reacts with limewater to form calcium carbonate which is insoluble in water. .
Gas
Glowing
wooden
splinter
Before
After
limewater
Gas
Before
After
Exercise:
Page 60Exersices 5.2 (all)
Buat semua 1,2 dan 3Buku amali
THE END