Hi everyone, my name is Ms. Panchal and I'm really excited and glad you decided to join me on our next science lesson.

So in as our lesson today, we're going to be focusing on how we can change state.

So we're looking from how we can get from a liquid to a solid.

And so.

we're going to use our knowledge of liquids and solids to help us understand that.

And so this lesson is part of our bigger unit of learning on an introduction to states of matter and changing states.

Let's get started with the lesson.

So the outcome for our lesson today is I can observe that some materials change states from liquid to solid when they are cooled.

So we're going to look at some keywords that we're going to use in our lesson today.

So we've got state, solid, liquid and freeze.

So what I'd like you to do is pause the video here and with your talk partner, take it in turns to read the definitions of these keywords.

When you've practised your reading and gone through the keywords and their definitions, click play and we'll start the lesson.

Great reading everybody.

Well done.

Now some of you might already be aware of some of these keywords and some of you might not be so sure, but don't worry 'cause we're going to talk through all of them in our lesson today.

So our lesson today is split up into two parts.

So the first part of the lesson, we're going to be looking at changing water from a liquid to solid state.

And then we're going to be looking at changing materials from liquid to solid states.

So let's get started with the first part of our lesson.

So Lucas and Sam are talking about how some materials can change state.

Explain to your partner what this means.

So pause the video here and have a little think on your own first and then talk to your partner about what changing state actually means.

Great ideas, everybody.

Well done.

So Lucas says, "I know that water can change state.

Water in solid state is called ice.

Ice can melt and change into water in liquid state." Sam says, "I have water in solid state in my freezer at home, but it hasn't changed into water in liquid state." What do I need to do for it to change state? So if Sam has water in a solid state in her freezer, but she would like to change it into a liquid state, what do you think she needs to do? So Jacob says you can change a state of water in solid state by changing its temperature.

And Lucas says, when we moved solid ice cubes from the cold freezer to the warmer room, they melted, changing into liquid water.

Sam says, can we change liquid water back to solid state by changing its temperature again? Pause the video here, have a think on your own and then share your ideas with your partner.

Can we change liquid water back to solid state by changing the temperature? So we can change the state of a material from liquid to solid by changing its temperature.

Sam says, do we need to keep heating water in liquid state for it to become solid again? Water is in liquid state at room temperature but becomes solid ice when it is cooled down.

Lucas says, we will need to put liquid water into the freezer where it is cold and it will change state.

So lots of us will have freezers at home and this is where we need to put the liquid water in order for it to change state.

Let's do a check of our learning.

How can you change the state of a material from a liquid to a solid? A, by changing its temperature.

B, by shaping it.

C, by cutting it.

What do we think is the answer? A, B or C? So good job everyone.

The answer is A, by changing its temperature.

So Lucas is measuring the temperature at which water in solid state becomes water and liquid state.

So Lucas says, solid water becomes liquid at zero degrees Celsius.

So if we have a look at his diagram here, we've got solid water and then at zero degrees Celsius it turns into liquid water.

Sam is measuring the temperature at which water in liquid states becomes water in solid state.

So Sam says, liquid water becomes solid at zero degrees Celsius.

So you've got liquid water turn into solid water at zero degrees Celsius.

Sam and Lucas realise that they have recorded actually the same temperature of zero degrees Celsius.

So liquid water becomes solid ice if it is cooled down.

And the change from liquid state to solid state happens at zero degrees Celsius.

This is the same temperature that solid ice becomes liquid water.

Let's do a check of our learning.

So water is in liquid state at room temperature but becomes a solid ice when it is A, cooled, B, shaken, C, heated or D, stirred.

Which do we think is the missing word? Great job.

The answer is A, cooled.

So water is in liquid state at room temperature but becomes solid ice when it is cooled.

Let's move on to the first task of our lesson today.

The children are discussing water changing between solid and liquid state.

Lucas says, zero degrees Celsius is the temperature that water changes from a solid state to a liquid state.

And Sam says, at zero degrees Celsius water changes from a liquid state to a solid state.

Do you agree with Lucas, Sam, or both of them and why? So pause the video here and have a little think.

Do you agree with what Lucas is saying, what was Sam is saying or both of them? But I'd also like you to have a little think about why.

You might want to write down your ideas or you might want to record yourself explaining what you think.

Pause the video, have a go and we'll talk through the answer really soon.

Fantastic ideas, everybody.

Well done.

So let's go through the answer.

So both children are correct.

So let's go over what Lucas and Sam had said.

So Lucas said, at zero degrees Celsius is the temperature that water changes from a solid state to a liquid state.

And Sam says, that zero degrees Celsius, water changes from a liquid state to a solid state.

So both Lucas and Sam are actually correct.

At temperatures below zero degrees Celsius, water is in its solid state and at temperatures above zero degrees Celsius, water is in its liquid state.

And zero degrees Celsius is the temperature at which it changes between the two.

Did you get an answer similar to this? Well done for having a good go at this task everyone.

So we've completed the first part of our lesson where we've been looking at changing water from liquid to solid state.

And we're now going to move on to changing materials from liquid to solid state.

Sam says, I know that when water is solid state changes to water in liquid state is called melting.

But Lucas says, what is it called the other way round, when water changes from liquid state to solid state? Do you know? Pause the video here and have a little think.

What is that process called? Do you know? Brilliant job everyone.

Well done.

So this process in which water in liquid state changes to water in solid state is called freezing.

Now freezers are used to freeze water.

Or water may freeze to become ice or snow when it is very cold.

Lucas says, can any other materials change from liquid state to solid state? What do you think? Have a little think in your head on your own and then share your ideas with your partner.

Can you think of any other materials that change from liquid state to solid state? Can you give me any examples? Great job.

So different materials can be observed changing from liquid to solid state when cooled.

Can you think of any examples? Great examples everyone.

Well done.

Just keep hold of those for now.

So when liquid butter is called, it becomes solid butter.

So here we've got two pictures.

We've got liquid state butter, we've got butter in a heated frying pan and we've got solid state butter that's maybe being kept outside or kept in the fridge.

But do all liquids change to solids at zero degrees Celsius? What do you think? Pause the video here and talk to your partner about it.

Do all liquids change to solids at zero degrees Celsius? Excellent ideas everyone.

Well done.

So different materials change from their liquid state to their solid states at different temperatures.

Some materials such as butter are in liquid state at higher temperatures but will change state as they cool it to be in solid state at room temperature.

Some materials such as ice cream will melt to be in liquid state at room temperature but are in solid state at colder temperatures.

Some materials like metals change state at temperatures much, much higher than a room temperature.

So here, we've got a picture of liquid metal at a very high temperature.

Lucas says, "Wow! I had no idea that metals could exist in a liquid state." So normally, day to day, we wouldn't really see metals in a liquid state because they have to be heated to a very, very high temperature, but it can be possible.

Lucas and Sam visited a local chocolate factory and met the chocolate makers that work there.

They're called chocolatiers.

And chocolatiers are people who make treats from chocolate.

And these chocolates often come in elaborate shapes and sometimes lots of different sizes as well.

Sam says, "I think they make the shapes by carving blocks of solid chocolate with a sharp knife." Do you agree with her? So Sam has said that she thinks there's a big block of chocolate and then they carve it in to make lots of different shapes and sizes and they use a knife to do it.

Do you agree with her or do you think something a little bit different? Great.

So actually it's different how they make these different types of chocolate.

So chocolatiers rely on the fact that chocolate can easily be changed between solid and liquid states.

They heat solid chocolate so it melts and changes to its liquid state.

So here, the process of heating has been used.

So they've got the solid chocolate and they're heating the solid chocolate so that it becomes liquid.

They pour the liquid chocolate into moulds of exciting shapes.

So we can see in the picture here, the chocolatier working with liquid state chocolate.

So they've obviously melted the solid chocolate into liquid and it's now going to be used in put into different moulds to make different shapes and also sizes of chocolate.

Finally, they let the liquid chocolate cool and become solid state again.

So we've gotten a bit of a cycle really.

So we've started with a solid chocolate and we've melted it in order to get the liquid chocolate and that's then called in order for the chocolate to be in the solid state again.

So Sam and Lucas have baked gingerbread people.

Do you like gingerbread people? I know, I really like them.

They want to decorate them with chocolate buttons, but they only have chocolates in solid square chunks.

So what could they do to change their chocolate from square chunks to round buttons? So pause the video here, have a little bit of thinking time on your own and then share your ideas with your partner and then share your ideas with the rest of the group.

How can Sam and Lucas go from square pieces of chocolate to round buttons? What could they do? I'll give you a little clue.

Have a little think about the learning we've just done about chocolatiers.

Excellent work everyone.

Hold onto that idea.

So let's do a check of our learning.

The process in which water in solid state changes to water in liquid state is A, melting, B, freezing or C, cooling.

What do we think is the correct answer? Brilliant job.

The answer is A, melting.

So the process in which water in solid state changes to water in liquid state is melting.

So let's do a check of our learning.

True or false? Different materials change from a liquid state to solid state when heated.

Do we think that's true or false? Great job.

The answer is false, but we need to think a little bit about why.

Is it because most materials cannot change from liquid state to solid state? Or is it because different materials change from liquid state to solid state when cooled? Which one do you think is correct? Great job.

So the reason is this is because different materials change from liquid state to solid state when cooled.

Great job everyone.

So let's move on to the next task for our lesson and this is a really, really exciting one.

So I would like you to become a chocolatier and make chocolate buttons with your knowledge of changing state.

So listen really carefully to the instructions and you might need an adult to help you with this.

So we're going to change solid state chocolate into liquid state chocolate.

So the first thing you're going to do is ask an adult to add 150 millilitres of warm water, no hotter than 50 degrees to a cup or beaker, and then ask an adult to wrap kitchen foil over the top of the beaker.

And you can use this example picture to help you.

Then I'd like you to place two chunks of chocolate on the foil and observe and note what happens over the next five to 10 minutes.

Once you've done that, we are gonna work on changing liquid state chocolate into solid state chocolate buttons.

So then I'd like you to place a piece of grease proof paper on the desk and then use a teaspoon to scoop up liquid chocolates from the silver foil.

You may need to ask a friend to hold the cup or beaker while you do this.

Then drizzle the chocolate into a circle shape on the grease proof paper and observe and note what happens over the next 10 to 15 minutes.

Now please be very careful as there is hot water involved, so please ask an adult to help you with this.

Have a go at this task and I can't wait to see the chocolate button that you've created at the end.

Off you go.

Amazing work everybody.

Well done.

I can see some really fantastic chocolate buttons that have been created.

So the first part of the task was changing solid state chocolate into liquid state chocolate.

So after a few minutes, the square of chocolate melted at the edges turning into a liquid.

And after 10 minutes, it had completely melted.

Did you find that as well? Great job.

Then moving on, the chocolate buttons were liquid to start with, then gradually they got harder and after 10 minutes, they were nearly solid chocolate.

Did you find that as well or did yours take a little bit shorter time or did yours take a little bit longer? Everyone's might vary a little bit, but well done for creating your chocolate buttons.

They look really delicious.

So let's do a summary of our learning for today's lesson.

So we can change the state of a liquid to a solid by changing its temperature.

Water is liquid at room temperature but becomes a solid ice when it is cooled down.

And the process in which liquid state water changes to solid state ice is called freezing.

And different materials can be observed changing from liquid to solid when cooled.

So we've done a lot of learning today about liquids and about solids, about how we can get from a liquid to a solid and I really enjoyed that chocolate example.

I think it made me really hungry actually.

I think I'm going to eat a little bit of chocolate now.

A huge well done for all of your work today.

I'm so impressed with all of the work that you've produced.

I hope you have a great rest of the day and I'm sure I'll see you very soon in the next science lesson.

Bye-bye.