procedures

Procedures...

Air Pressure

You will need:

a funnel

a bottle

vinegar

a balloon

baking powder

1. Place the funnel in the neck of the bottle and pour in some vinegar, about half way up.

2. Place the funnel in the neck of the balloon. Carefully trickle some baking powder into it.

3. Fit the neck of the balloon carefully over the bottle, letting the powder filled part hang down. Gently turn the main body of the balloon over.

4. Tip the baking powder into the vinegar. The balloon blows up as the mixture starts to fizz.

5. The fizzing shows that a chemical reaction is taking place between the vinegar and the baking powder. This reaction makes a lot of gas. As more gas is a produced its pressurises. The rising gas pressure forces the balloon to expand.

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Measuring Temperature ~ Make a thermometer

You will need:

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A jug of water

A bottle

Food colouring

A clear straw

Re-usable adhesive

A piece of card

Scissors

A felt tip pen

1. Pour cold water into the bottle until it is about two-thirds full. Add some colouring. Dip the straw into the water and seal the neck tightly with reusable adhesive.

2. Blow down the straw to force extra air into the bottle. After a few seconds, the extra air pressure inside will force the water level to rise up the straw.

3. Cut the card and slot it over the straw. Let the bottle stand for a while. Make a mark on the card by the water level to show room temperature. Now your thermometer is ready to take outside into the sunlight- that is- if the sun is shining!

4. The sun's heat will make the air and water in the bottle expand. This will force the water level in the straw above the room temperature mark. Now put your thermometer in the refrigerator for two hours. The water level will drop below the room temperature mark. Make a note on your thermometer.

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1. Place the funnel in the neck of the bottle and pour in some vinegar, about half way up.	2. Place the funnel in the neck of the balloon. Carefully trickle some baking powder into it.
3. Fit the neck of the balloon carefully over the bottle, letting the powder filled part hang down. Gently turn the main body of the balloon over.	4. Tip the baking powder into the vinegar. The balloon blows up as the mixture starts to fizz.
5. The fizzing shows that a chemical reaction is taking place between the vinegar and the baking powder. This reaction makes a lot of gas. As more gas is a produced its pressurises. The rising gas pressure forces the balloon to expand.

1. Pour cold water into the bottle until it is about two-thirds full. Add some colouring. Dip the straw into the water and seal the neck tightly with reusable adhesive.	2. Blow down the straw to force extra air into the bottle. After a few seconds, the extra air pressure inside will force the water level to rise up the straw.
3. Cut the card and slot it over the straw. Let the bottle stand for a while. Make a mark on the card by the water level to show room temperature. Now your thermometer is ready to take outside into the sunlight- that is- if the sun is shining!	4. The sun's heat will make the air and water in the bottle expand. This will force the water level in the straw above the room temperature mark. Now put your thermometer in the refrigerator for two hours. The water level will drop below the room temperature mark. Make a note on your thermometer.