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Hi everyone.

My name is Ms. Panchal here.

I'm so excited and glad you decided to join me on this Science lesson.

So our learning today is going to be focusing on changing states of matter, and we're going to focus on changing from a solid to a liquid.

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

So we're going to use your knowledge of solids, liquids, and gases to help us with our learning today.

Let's get started with the lesson.

So the outcome for our lesson today is "I can observe that some materials change state from solid to liquids when they are heated." So our focus today is looking at solids and liquids, and looking at when solids are heated.

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

So I'm gonna talk to you about them a little bit.

So we've got a solid, state, liquid, heat, and melt.

So what I'd like you to do is pause the video here, and take it in terms with your talk partner to have a go at reading each of the definitions of the keywords.

Once you're ready and have done your reading, can you click play on the lesson and we'll continue with our learning for today.

Off you go.

Great reading everybody.

Well done.

Now some of you might already have a good understanding of some of these keywords, but don't worry if you are not too sure because we're going to be using all of them in our lesson today.

So today's lesson is split up into two parts.

So we're first going to think about water in solid and liquid states, and then we're going to move on to other changes from solid to liquid.

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

So after finishing her juice, Izzy had some ice cubes at the bottom of her glass.

After a while, she noticed that the ice cubes were no longer there, what's happened to them? So pause the video here, and have a think with your talk partner, what's happened to the ice cubes that were in the bottom of Izzy's glass? Great job everyone.

Great ideas.

Maybe this has happened to you before as well.

So Izzy says, "There is a pool of water in the bottom of my glass now.

The ice cubes were water in solid state, and they have changed to water in liquid state." Jacob says, "But what does state actually mean?" So pause the video here, and have a little think on your own in your head, and then share your ideas with your talk partner.

What does state mean? Great ideas everyone.

Well done.

Keep those in your head for now.

So the state of a substance or material is the form in which it can exist, and these are a materials in a range of different states and the balloons can take gas.

So we've looked at previously, and you may have looked at this in your other science lessons, different states of matter.

We've got solid, liquid, and gas, and there are three common states known as states of matter.

And we've just said what they are.

Can you repeat them for me? Excellent, well done.

Solid, liquids, and gases.

So the three common states of matter are solid state, liquid state, and gas state.

So for example, solid state wood, liquid state soap, and gases in the air are an example of gases.

We can see water in all three states in our daily lives.

What do we call water when it's in its solid state? Do you know? Write your idea down on a whiteboard.

What do we call water when it's in a solid state? Excellent, well done.

So water in a solid state is known as ice.

Now can anyone tell me or have a little think in your head about when would we might use ice? When might be a good time? Excellent.

Well done.

So if you want to make a cold drink, if it's a hot summer's day or if you're having a party and you want to keep lots of drinks cold, sometimes people have a bucket of ice to keep the drinks cold.

Water in a liquid state is known as water.

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

The ice cube from Izzy's drink was a solid in the freezer.

The temperature in the freezer was less than 0 degrees Celsius.

Water is a solid ice at 0 degrees Celsius, but changes state to be a liquid when it is heated.

Izzy says, "But I didn't put my ice cubes on a stove or over a flame.

So how were they heated? Do you know?" So we've learned here that the ice has melted.

So we know that water, the solid ice at 0 degrees Celsius, but changes state to be a liquid when it is heated.

But Izzy has not put any heat directly on the ice cubes.

So how do we know? Excellent.

We'll come back to that in a moment.

So how can you change the state of a solid to a liquid? Let's answer this question as our check of learning.

Is it A, by changing its colour? B, by changing its temperature? C, by changing its mass? Or D, by changing its name? Brilliant, the answer is B, by changing its temperature, and we're going to look at that in more detail in the later part of our lesson today.

So the temperature in Izzy's room was much higher than in a freezer.

So although she didn't put it under a flame or put it on a stove, actually the room temperature where Izzy's glass was was actually much higher than in the freezer.

The air in the room heated up the ice cubes so they changed from a solid state to a liquid state.

So we can see here we've got ice cubes melting, and it's changing from a solid state to a liquid state.

If they have different names, does that mean ice and water are different substances? So we've got two pictures here to show the before and after.

So we can see here that we've got an example of liquid water and we've also got example of solid water as ice.

But Izzy's saying, "If they have different names, does that mean water and ice are different substances or are they the same?" So water and ice are the same substance, it's just that they are in different states, so they are the same substance.

It is a bit confusing when we only call it water when it's a liquid, even though it is water all the time just in different states.

So it is a little bit tricky to get your head around, but you're doing such a fantastic job everyone so far.

Well done.

There is something else though that we often see in the winter that is water in the solid state.

So I want you to pause the video here, have a little think on your own in your head, and then with your talk partner.

There is something else that we often see in the winter that is water in the solid state.

Does anyone know what it is? Brilliant job, everyone.

Well done.

It's actually snow.

So snow is also water in a solid state.

Let's do a check of our learning.

When ice is heated, it changes state to be A, liquid water? B, liquid engine oil? C, liquid gas? Or D, liquid milk? Which one do we think is correct? A, B, C, or D? Brilliant job everyone.

Well done.

The answer is, a, liquid water.

So when ice is heated, it changes state to B, liquid water.

Let's do another check of our learning.

At what temperature does solid water ice become a liquid? So A, 100 degrees Celsius? B, 50 degrees Celsius? C, 0 degree Celsius? Or D, 25 degrees Celsius? Which one do you think is correct? Brilliant.

The answer is C, 0 degrees Celsius.

So let's move on to the first task of our lesson.

So what I'd like you to do is put some ice cubes on a saucer and make observations as it heats up and changes from water in the solid state to water in the liquid state.

So find a plate and put some ice cubes on it, and I want you to think really carefully about what you can see, and I'd like you to write down some of those ideas.

So pause the video here, have a go at this task, and I'm really looking forward to hearing about all of your observations.

Off you go.

Excellent work everybody.

Well done.

I'm so impressed with the writing you've done about the observations.

So your observations may have been like this.

As the ice melted, the cubes got smaller and looked more rounded.

As they got smaller, a pool of liquid water formed around them.

Did you get the same observations? Well done everyone.

So we've come towards the end of our first part of our lesson.

So we've looked at water in solid and liquid states, and we're going to use that knowledge to help us now look at some other changes from solid to liquid.

So Jacob says, "What do you call it when a solid changes to a liquid?" What do you think? Write your ideas down on a whiteboard.

What do you call it when a solid changes to a liquid? Brilliant.

The process in which a solid changes to a liquid is called melting.

And we can see it melts snowman here, which sadly, unfortunately, is melting ice.

Ice, solid water, melts and changes to liquid water at 0 degrees Celsius.

Ice is not the only material that can melt.

Can you name any others? And if you're struggling, have a look at the picture on the board there to give you a little clue.

Can you name any other examples? Brilliant work everyone.

Well done.

So Izzy's example is ice cream.

Well done.

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

Water changes from solid state to liquid state when you take it out of a freezer and put it in a room because the temperature in the room is warmer than the temperature in the freezer.

We call the level of heat in a room, room temperature.

Room temperature varies, but generally it is between 50 degrees Celsius and 22 degrees Celsius.

So that's a lot warmer than the temperature inside your freezer.

Jacob says, "So ice melts at room temperature." Not all materials melt at room temperature.

Some materials change from a solid state to a liquid state at other temperatures.

Can you think of anything else that is solid at room temperature but melts at higher temperatures? Pause the video here, have a little think on your own, then share your ideas with your partner and then with the rest of the group.

Can you think of anything else that is a solid at room temperature but melts at a higher temperature? Can you gimme some examples? Great job.

So butter is an example.

So butter is a solid state when it's placed on the side in the kitchen that melts to a liquid state in a frying pan when heated on a cooker.

So let's have a look at the two pictures to help us understand that.

So solid butter, room temperature.

If you've got butter on the side in your kitchen ready to maybe spread on your toast, and then when you put butter in a pan, in a frying pan, it then turns into a liquid.

So Izzy has a question.

"When we take frozen peas out of the freezer and place them in a room, do they melt?" Pause the video, have a little think, what do you think? Do they melt? Excellent.

Well done.

So in the freezer, peas contain frozen water and the water is in its solid state, which is ice.

And when we take the peas out of the freezer and heat them, the water inside the peas melts into liquid state water, but the peas themselves are still solid.

And this is what we call defrosting.

Has anyone heard that word before? Defrosting.

Great job.

So let's check.

Do a check of our learning.

What is the name of the process in which a solid changes to a liquid? Is it A, freezing? B, boiling? C, cooking or D, melting? Which one do you think is the correct answer? Brilliant.

The answer is D, melting.

Let's go on to another question.

Different materials can be observed changing from solid to liquid when A, heated, or B, cooled.

Which one do you think is the answer? Excellent job.

The answer is A, heated.

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

So let's move on to the next task for our lesson today.

So I would like you to observe which solids melt at room temperature.

The first stage, A, I'd like you to predict which you think will melt at room temperature.

B, put a small amount of each material on a saucer, and then C, observe each material, and after 15 minutes, record your findings.

So you might like to try some of these solids.

Ice, butter, cheese, ice lolly, candy lolly, frozen peas, wood, and metal.

So pause the video here and have a go at the task.

I'm really looking forward to hearing about all the things you observed.

Off you go.

Brilliant work everyone.

Well done.

And I'm so impressed with all of your observations, and I can see some beautiful handwriting as well.

So your results may have been like this.

"The butter was a solid when we took it out of the fridge, and it was hard to squash, but after 15 minutes, it was easier to squash.

It was still a solid but softer." "The cheese was a solid, which you couldn't squash, when we took it out of the fridge.

It hadn't changed after 15 minutes." Another example, "The ice lolly was a hard solid when we took it out of the freezer, and it began to melt after about a minute.

After 15 minutes.

it was mostly in its liquid state.

The colour stayed the same." "The candy lolly was a hard solid at the start and didn't change." Did you get some of these observations too, or did you get different ones? Well done by having a good go.

Another example may have been the pea.

So "The pea was a hard solid, which we couldn't squash when we took it out of the freezer.

After 15 minutes, it was sitting in a pool of water that must have been from the ice inside it that had turned into water, and the pea itself was still solid but could be easily squashed." And this was linked to our earlier example in the lesson.

"Nothing happened with the wood or metal." Did you get those observations too, or did you get slightly different ones? So we've come towards the end of our lesson today.

So let's do a summary of our learning.

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

Water is a solid ice at 0 degrees Celsius, but becomes a liquid when it is heated.

The process in which a solid changes to a liquid is called melting, and different materials can be observed changing from solid to liquid when heated.

So we've done lots of different learning here today, all about solids to liquids, and we've looked at lots of different examples.

So next time maybe you're in the kitchen and you see an ice cube, and you see what happens if you leave it in your drink, and you now you know what happens and why it happens.

Well done for all of your work today, everybody.

You've worked incredibly hard, and you've had to go at the tasks.

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

Bye-bye.