The atmosphere is the layer of gases around the earth These
gases are known as air
Slide 3
Air Do the percentages of the gases ever change in air?
Slide 4
Is the atmosphere heavy? Does the atmosphere have mass? Is it
heavy? Yes it does Yes its weight is equal to a layer of water
10.36m thick surrounding the entire surface of the earth So why
doesn't it crush us?
Slide 5
Filling balloons Which gas is more dense? CO 2 Oxygen What is
density? Density= Mass/Volume Hydrogen peroxide Test tube Balloon
0.2g of Manganese dioxide Hydrogen peroxide + Manganese dioxide
Oxygen
Slide 6
Carbon dioxide balloon Fill the test tube half way with vinegar
Put 3-4 teaspoons of baking soda into a balloon Attach the balloon
to the test tube and allow the balloon fill up with gas CO 2
Slide 7
Oxygen Balloon Very carefully add two 5ml droppers of hydrogen
peroxide to a test tube Carefully weigh 0.2-0.3g of manganese
dioxide and add it to a balloon Attach the balloon to the test tube
and allow the manganese dioxide to fall into the test tube leave
for about 8-10mins to allow the balloon to fill Manganese dioxide
is a catalyst A catalyst is a substance that speeds up a chemical
reaction but does not get used up Oxygen Hydrogen peroxide Test
tube Balloon 0.2g of Manganese dioxide Hydrogen peroxide +
Manganese dioxide Oxygen
Slide 8
35mm film canisters Tidy away books and put mat down on desk
Fill the canister full with vinegar Put a full spoon of baking soda
onto a small square of j-cloth Wrap the cloth into a parcel Drop
the parcel into the vinegar and very quickly put on the lid and
turn canister upside down on table Fill in section A of worksheet
based on your observations
Slide 9
Uses of carbon dioxide Fizzy drinks Fire extinguishers Stage
effects
Slide 10
Animation of oxygen Fill in section B of worksheet based on
your observations