Heating Materials 2 Worksheet

You use so many different things every day and they are made out of an enormous range of different materials.

Some of those materials can be changed by heat. Sometimes it might be a lot of heat, sometimes it might be just a little bit. Sometimes they change back when they cool down.

In this worksheet have a think about the materials in the question, what you know about them, and use that to help you decide how the materials change.

To start to melt an ice cube, what would you need to do?

leave it in a warm room

put it on a hot radiator

heat it in a very hot furnace

To start to melt a plastic bag, what would you need to do?

leave it in a warm room

put it on a hot radiator

heat it in a very hot furnace

To start to melt a lump of metal, what would you need to do?

leave it in a warm room

put it on a hot radiator

heat it in a very hot furnace

What will happen to some melted chocolate if you leave it in a cool room?

the cat will eat it

it will stay the same

it will turn into solid chocolate

What will happen to a piece of toast if you leave it in the toast rack?

it turns back into bread

it stays the same

it will melt

How can you change a melted ice cube back into a piece of ice?

leave it in a cool room

you can't change it back

put it in the freezer

What will you have to do to make a candle melt?

burn it

put it on a hot radiator

put it into a hot furnace

If ice cream is left out of the freezer it will melt and turn into a liquid.

Girl eating ice cream

Which of the following will turn into molten ice cream quickest?

a tub of ice cream

ice cream in a cornet

spoonful of ice cream in a bowl

You accidentally drop a birthday card into the fireplace and it catches fire.

How can you get the birthday card back?

there's nothing you can do to change it back

by putting it into the fridge

by leaving it to cool down

In the Second World War some tanks were used for fighting in the deserts of Africa.

Desert tank

The soldiers found that the metal of the tanks became so hot in the sun, they could cook something on the metal surface.

What do you think they cooked?

roast chicken

eggs

chips

ANSWERS

Question 1

To start to melt an ice cube, what would you need to do?

CORRECT ANSWER

leave it in a warm room

EDDIE SAYS

Ice is frozen water - it only needs to warm up a little and it\'ll start to melt. Hold it in your hand - that\'ll do it. After it has snowed, it only needs the temperature to rise a little and the snow starts to melt.

ANSWERS

Question 2

To start to melt a plastic bag, what would you need to do?

CORRECT ANSWER

put it on a hot radiator

EDDIE SAYS

A hot radiator is enough to start changing a plastic bag - mind you, one of those hot electric radiators is best. As it gets hot, the plastic starts to change shape and some of it melts into a new shape. In a furnace the plastic would simply catch fire and turn to gas.

ANSWERS

Question 3

To start to melt a lump of metal, what would you need to do?

CORRECT ANSWER

heat it in a very hot furnace

EDDIE SAYS

Most metals need a very high temperature to melt them. Just as well, because we use lots of things made of metal and we wouldn't want our spoons and scissors melting in the room!

ANSWERS

Question 4

What will happen to some melted chocolate if you leave it in a cool room?

CORRECT ANSWER

it will turn into solid chocolate

EDDIE SAYS

Chocolate is one of those things that you can make melt and freeze quite easily. On a hot day, you take a choccy bar out of your bag and you can feel it's all gooey. Put it in the fridge for half an hour and it'll be nice and solid and ready to eat.

ANSWERS

Question 5

What will happen to a piece of toast if you leave it in the toast rack?

CORRECT ANSWER

it stays the same

EDDIE SAYS

Once bread has been heated and turned into toast, that's it! It won't change any more. It might be a bit soggy and floppy after a while, but it won't change back into bread. You'll learn to call this a PERMANENT change.

ANSWERS

Question 6

How can you change a melted ice cube back into a piece of ice?

CORRECT ANSWER

put it in the freezer

EDDIE SAYS

Water is easy to change into ice and back again: in the freezer it's cold enough to make water into solid ice. Put that ice in a warm room and it'll melt into water. Put THAT back into the freezer and hey presto it's ice again after an hour or so!

ANSWERS

Question 7

What will you have to do to make a candle melt?

CORRECT ANSWER

put it on a hot radiator

EDDIE SAYS

Candles are made of wax. To make the wax melt it just needs to be quite hot - in fact a windowsill on a sunny day will do it, so a radiator is fine. If you burn the candle it changes into some gases and isn't wax any more.

ANSWERS

Question 8

If ice cream is left out of the freezer it will melt and turn into a liquid.

Girl eating ice cream

Which of the following will turn into molten ice cream quickest?

CORRECT ANSWER

spoonful of ice cream in a bowl

EDDIE SAYS

The smallest quantity will change fastest. That's because the warmth can reach more of it at the same time. The ice cream on the edge of the tub will have melted long before the ice cream in the middle. Your cornet can seem to melt quickly on a hot day, but the spoonful in the bowl will be fastest because it's more spread out and there's less of it.

ANSWERS

Question 9

You accidentally drop a birthday card into the fireplace and it catches fire.

How can you get the birthday card back?

CORRECT ANSWER

there's nothing you can do to change it back

EDDIE SAYS

Sad! Once paper or card has burned, that's it! It's changed permanently into ash and gases and there's nothing you can do to change it back.

ANSWERS

Question 10

In the Second World War some tanks were used for fighting in the deserts of Africa.

Desert tank

The soldiers found that the metal of the tanks became so hot in the sun, they could cook something on the metal surface.

What do you think they cooked?

CORRECT ANSWER

eggs

EDDIE SAYS

In fact they were able to break an egg on to the flat surface of their tank and the hot metal acted like a frying pan and the egg began to cook. How hot must it have been INSIDE the tank?! Even that amount of heat is not enough to cook either chicken or chips.