Hi, everyone.

My name is Ms. Panchal.

I'm really glad and excited that you decided to join me in our science lesson today.

So our lesson today is going to be focusing on some more irreversible changes.

And this lesson is part of our bigger unit of learning on properties, changes, and separating materials.

Now, you may already have an idea of what irreversible changes are, but our lesson today is going to give you a little bit more information, but also some more examples for you to help understand the idea.

So let's get started with the lesson.

So the outcome for our lesson today is "I can describe the action of acid with bicarbonate soda as an irreversible change, where a new material is formed." So in our lesson today, we're going to come across quite a few keywords.

So what I'd like you to do is pause the video here, and I would like you to read the keywords and the definitions firstly to yourself in your head, and then I would like you to take in turns with your partner to read out the definitions to each other.

Once you've done that reading, click play and we'll continue with the lesson.

Off you go.

Great job, everyone.

Well done.

It's really important when we're looking at new keywords for our lesson, we're able to say them, but also that we have an understanding of what they mean as well.

So we're going to come across lots of these words in our lesson today.

And some of you might already have an understanding of these words before, but may have used them before in your learning as well.

So our lesson today is going to be made up of two different parts.

So we're first going to be looking at mixing bicarbonate of soda and vinegar, and the next part of our lesson is fizzing is evidence of an irreversible change.

So let's get started with the first part of the lesson where we're going to be looking at mixing bicarbonate of soda and vinegar.

So Lucas and Sofia have been making model volcanoes in their geography lessons.

Their teacher showed them how to make it look like a volcano is erupting by mixing a powder and a liquid in a recycled glass jar placed inside the model.

Have you ever tried this? And do you know what the powder and the liquid were? So maybe you've completed this investigation or model before in your learning.

What do you use? Great job.

Some of you may have used some things that are similar, and some of you may have used some other different materials as well.

So the volcano model uses a mixture of vinegar and bicarbonate of soda.

Where might you find these ingredients? So have a little think.

We've got vinegar and bicarbonate of soda.

Where do you think you might find these ingredients? Great, so Lucas says, "We have vinegar at home to put on our chips or on salad dressing." And Sofia says, "I think my dad uses bicarbonate of soda in baking." So vinegar is a type of acid, and some acids are found in nature.

So, for example, lemons, oranges and grapefruit contain a type of acid.

So things that contain quite a lot of acids have quite a strong flavour.

Some acids are much stronger than others.

And acids can often be found in our kitchens.

And acids have a sour taste.

As I was saying, it's quite a strong taste, it can be quite sour.

Some people love it, and some people don't love it.

Honey contains a small amount of acid, but it doesn't taste sour because it contains lots of sugar.

So you can add things to some of these things that have acid in, and it will change the flavour.

Acids can also be found in our bodies.

Stomach acid kills microorganisms in the food that we eat.

So inside our stomach there is something called stomach acid, and that helps us to break down our food that we eat, but it also kills any of those microorganisms in the food that we eat.

And it helps us also to digest the food that we have.

Many acids are not safe to eat or drink.

And some acids can be highly poisonous and very, very dangerous.

And this is a sign warning of poison.

So be really, really careful when you are around acids, to make sure that you know how to be safe around them.

The acid used in cells and batteries would make you very ill if you tasted it, or it could burn your skin.

So some acids are completely safe and some acids can be very, very harmful.

So it's really important that you are safe.

Let's do a check of our learning.

"Vinegar is an example of an that we find in our home." Is the missing word A, solution, B, fertiliser, C, acid, or D, liquid? What do you think? Great.

Well done, everyone.

The answer is C, acid.

So, "Vinegar is an example of an acid that we find in our home." So let's move on.

Bicarbonate of soda is a kitchen ingredient used in baking.

Know I've definitely used bicarbonate of soda when I've been baking before.

Now, bicarbonate of soda comes as a white powder.

And bicarbonate of soda is commonly used in recipes to make bread, butter, and cakes rise when it's baked.

So let's do a check of our learning.

"Which powder is most likely to be bicarbonate of soda?" So think back to the learning we've just done on the previous slide.

"Which powder is most likely to be bicarbonate of soda?" Do we think it's A, B, or C? Have a little think.

Great job, everyone.

Well done.

The answer is A.

Let's do another question to check our learning.

"What is bicarbonate of soda commonly used for?" A, to make cakes rise, B, to add colour to food, C, to add a sweet flavour, or D, to keep food moist? What do we think is a correct answer, A, B, C, or D? Excellent job, everyone.

Well done.

The answer is A, to make cakes rise.

So let's move on to the first part and task for this lesson.

Observe what happens when you mix bicarbonates of soda and vinegar.

So I'm going to talk you through the steps now.

So the first thing is to do is to place a clear beaker on a tray or in a bowl.

And then I would like you to add 50 millilitres of white vinegar to the beaker.

Then I would like you to add two teaspoons of bicarbonate of soda to the vinegar.

So measure out, then add all at once.

Then I would like you to record your observations.

When recording your observations, I would like you to have a think about what happened and what evidence is there that a new material is being produced.

So pause the video here, and you may need to ask an adult to help you do the measuring and to get your beaker and tray or bowl ready.

Pause the video here, have a go at the investigation, and I'm looking forward to hearing what you saw happen and what evidence that there is a new material that's being produced.

Have a go at this task and click play when you're ready to continue.

Excellent work, everybody.

Well done.

I can see you've really followed the clear steps on how to set up the investigation, and you were looking really clearly at what was happening.

So, your answer may looked a little bit like this.

When we added the bicarbonate of soda to the vinegar, bubbles appeared and the mixture rose up the beaker and spilled out of the top.

It looked like foam.

I think a new material must have been produced because I could observe bubbles that were not there before.

So, did you also observe the foam or did you observe something different? Well done for following those steps of setting up the investigation.

I hope that you found lots of interesting ideas from this investigation, and maybe you saw foam as well.

So, we've finished the first part of our lesson where we looked at mixing bicarbonate of soda and vinegar, and both of those things are things that we would find in our kitchen.

And we said that bicarbonate of soda is used to help cakes rise, and vinegar is quite acidic and it's used on food and also in salad dressings.

But we also said that acid can be found in lots of other things as well, including our bodies.

And we spoke about the fact that actually, in our stomach, we have acid in our stomach to help us break down our food.

So we are going to use that learning to help us with the next part of the lesson.

So we're now going to move on looking at fizzing is as evidence of an irreversible change.

So when the vinegar and bicarbonate of soda are mixed, this produces a new material.

And you might have heard the sound of the new material fizzing.

Did you hear a fizzing sound when you mix the vinegar and bicarbonate soda? You will have observed the new material frothing and foaming.

Do you know what that new material is? So it's very clear that when we've mixed vinegar and bicarbonate of soda, a new material has been produced.

You may have heard the sound of some fizzing, and you would've seen some frothing or foaming.

But do you know what this new material is? Have a think in your head on your own and then share your answer with your partner.

And then I would like you to share your ideas with the rest of the group.

Do you know what the new material is? Great job and great discussion, everybody.

Well done.

So Sofia says, "I think the new material is air because I observed lots of bubbles being produced." Lucas says, "I think the new material is a liquid because the vinegar rose up inside the beaker and flowed over the top." "Maybe the new material is a gas because I heard a fizzing sound like gas being released." What do you think? Excellent work, everybody, well done, and well done for sharing your ideas.

So a bubble is a gas contained within a liquid.

So we've got a diagram here to help us.

We've got a bubble, we've got the liquid on the outside, and we've got gas on the inside.

When bicarbonate of soda mixes with an acid such as vinegar, this produces a new material in the form of a gas.

The gas produced is called carbon dioxide.

And you may have heard carbon dioxide word before.

Lucas says, "We have learned about carbon dioxide gas in other science lessons," and maybe you have learned about it before as well.

So carbon dioxide gas occurs in Earth's atmosphere.

It is the gas that plants need when they make their own food using photosynthesis.

And it is also exhaled or breathed out as a waste gas by animals including humans.

The bubbles in fizzy drinks are carbon dioxide.

We've got a fizzy drink, and all those bubbles that you can see are all carbon dioxide.

When the bottle or can are sealed, the gas is dissolved in the liquid.

And when you open the lid, the dissolved carbon dioxide turns into a gas and the bubbles appear.

Let's do a check of our learning.

What's happens when vinegar and bicarbonate of soda are mixed? Do we think A, nothing happens, B, a new product is produced, C, the vinegar turns red, or D, a solution is produced? So pause the video here, have a think about the learning we've done today.

Have a think about your investigation.

If you need to, go back to your investigation or go over the slides that we've done earlier in the lesson today to help you answer the question.

Click play when you're ready to continue and we'll go through the answer.

Super learning, everybody.

Well done.

So, our question was, "What happens when vinegar and bicarbonate have soda are mixed?" And we know that a new product is produced.

Did you get the same answer? Super job, everyone.

Let's go on to another question to check our learning.

"What gas is produced when vinegar and bicarbonate of soda are mixed?" A, carbon monoxide, B, oxygen, C, nitrogen, or D, carbon dioxide? Which one do you think is produced when vinegar and bicarbonate of soda are mixed? As I said with the previous question, if you need to, pause the video here, go back to the last couple of slides to go over the learning before you complete the question.

Click play when you're ready to continue and we'll go through the answer.

Great job, everyone.

The answer is D, carbon dioxide.

Well done, everyone.

So the change that Lucas and Sofia observed can be written like this, acid add bicarbonate of soda gives us carbon dioxide and other materials.

Do you think the change that has taken place can be reversed? Why do you think this is? So pause the video here and have a think about what is being asked.

Do you think the change that has taken place can be reversed? So can we go backwards? Can we get our acid and bicarbonate of soda back? Pause the video here, have a think on your own, and then share your idea with your talk partner.

Click play when you're ready to continue.

Excellent discussion, everybody.

And I'm really impressed with all the ideas you've come up with.

Well done.

So Lucas says, "Can we change the bubbles and the liquid mixture left behind back into vinegar and bicarbonate of soda again?" When a new material has been made, the changes are irreversible.

This means that the material that has been changed cannot return to its original state.

The changes cannot be reversed, so we cannot get back to our original materials.

Let's do a check of our learning.

"Acid reacting with bicarbonate of soda is change." So in that gap, is it A, irreversible change, B, an irreversible change, or C, a state change? Have a little think.

Super work, everyone.

Well done.

So we're saying here that acid reacting with bicarbonate of soda is an irreversible change.

So we cannot get the original materials back, and a new product and new material has been made.

Let's do another check of our learning.

True or false? During an irreversible change, the original material cannot return to its original state.

Do we think that's true or false? What do you think? Super job.

We know the answer is true.

And we now need to think about why that is true.

Is that because A, a new product is produced so the original material no longer exists, or B, the original material has all evaporated? So think back to what are irreversible changes, and think back to the example that we've just investigated.

Which answer do you think is correct, A or B? Great job.

The answer is A.

So a new product is produced so the original material no longer exists, and were not able to go back to the original material.

Well done, everyone.

So let's move on to the next part of the lesson and the next task.

So, collect evidence to show that a new material is produced when an acid is mixed with bicarbonate of soda.

So the first thing I would like you to do is put 50 millilitres of vinegar into a beaker.

And the second step is I would like you to put two teaspoons of bicarbonate of soda into the fingers of a disposable glove.

Then I would like you to carefully place the opening of the glove on top of the beaker, making sure that the powder does not fall in.

Then I would like you to lift up the fingers of the glove to release the bicarbonate of soda into the vinegar so it mixes together.

Observe what happens.

So I would also like you to now think about explaining how your observations can be used as evidence that a new material, which is a gas, is produced during this change.

So you've done the investigation now and you've observed what has happened.

So I'd like you now to explain how your observations can be used as evidence that there is a new material that has been produced during this change.

So, when explaining, you can maybe talk into a camera and record yourself.

You could maybe write it down or jot it down on some Post-It notes.

Or you can even share your ideas with your partner.

You choose how you would like to record your work.

Click play when you're ready to continue and we'll go through an example answer.

Great job, everyone.

Well done.

I can see you've worked really hard to explain how this observations can be used as evidence, but I can also see that you use lots of keywords.

So well done, everybody.

So your answer may look a little bit like this.

When the bicarbonate of soda was added to the acid, bubbles were produced and the mixture rose up the beaker.

At the same time, the glove began to inflate.

This happened because the glove was being filled with carbon dioxide, and this can be used as evidence that a gas is being produced.

So you would've observed that over time, the glove actually inflated.

And this is because the gas carbon dioxide was produced when the bicarbonate of soda and the acid were mixed together.

So, did you get a similar explanation or did you get a different one? Well done by having a good go at this task, everybody.

I know there were quite a few different keywords for you to include, but I'm really impressed with your writing.

So, we've come towards the end of our lesson today, learning about more irreversible changes.

So let's do a summary of what we have learned in lesson today.

So we've learned that vinegar is an example of an acid that we find in our homes.

We know that bicarbonate of soda is a white powder used in baking to make bread, butter, and cakes rise when baked.

When vinegar and bicarbonate of soda are mixed, this produces a new material in the form of a carbon dioxide gas.

And the action of acid with bicarbonate of soda is an irreversible change.

And during an irreversible change, the material that has been changed cannot return to its original state.

And that's something that's really important with an irreversible change, we cannot return to its original state.

Now, well done, everyone, for all of your hard work today.

I know there were lots of keywords that we spoke about, but I'm really impressed with all of your learning and all of the work that you have produced.

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

Buh-bye.