Gases and Gas Preparation Flashcards
What is the atmosphere composed of?
78% Nitrogen
21% Oxygen
nearly 1% Argon
0.04% Carbon dioxide
How can you use Iron to determine the percentage of Oxygen in the air?
Put wet Iron wool in a test tube.
Invert the test tube and put it into a beaker of water.
Measure the initial column of air.
Leave the experiment for a week.
Measure the end column of air.
Use this to calculate the percentage of Oxygen in the air.
What formula is needed to calculate the percentage of Oxygen?
(Start volume − Final volume)/Start volume
How can you use Copper to determine the percentage of Oxygen in the air?
Place the Copper in a tube which is attached to a gas syringe at either end. One syringe should have air, one shouldn’t.
First heat up the mound of copper powder with a Bunsen burner on a blue flame.
Continually push the air over the heated copper powder with the gas syringes.
Continue until the reading on the syringe doesn’t change.
Using the syringes measure the volume of the remaining air.
What happens when you burn something?
It is reacting with the Oxygen in the air.
What does the thermal decomposition of Metal Carbonates always produce?
Carbon Dioxide + Metal oxide
What is the definition of thermal decomposition?
Thermal decomposition is when a substance breaks down into simpler substances when heated.
How do greenhouse gases work?
They absorb most of the heat that would have been radiated to space. Then the gases re-radiate it in all directions - including back to Earth.
How do greenhouse gases work?
They absorb most of the heat that would have been radiated to space. Then the gases re-radiate it in all directions - including back to Earth.
What is the test for Chlorine?
Bleaches damp blue litmus paper, turning it white (my turn red for a moment).
What is the test for Oxygen?
Oxygen relight a glowing splint.
What is the test for Carbon Dioxide?
Carbon Dioxide makes limewater turn cloudy.
What is the test for Hydrogen?
When a lit splint comes in contact with Hydrogen it will give of a ‘squeaky pop’ sound.
What is the test for Ammonia?
Ammonia turn damp red litmus paper blue, (also has a very strong smell).
What is the test for water?
Water will turn white anhydrous copper(II) sulphate to blue hydrated copper(II) sulphate. Won’t tell you if the water is pure.
