Welcome to today's lesson on bunsen burners.

It's from the unit, Solid liquid gas states and changes of state.

We're going to look at bunsen burners today, and by the end of the lesson you should be able to tell me how to light a bunsen burner safely and control the temperature of the flame.

I'm really pleased that you've come along to learn with me.

Don't worry if you don't know anything about bunsen burners.

We're going to go through this lesson step by step, and by the end of it you're gonna be an expert.

Here are today's keywords.

They are bunsen burner, collar, safety flame, blue flame, splint.

On the next slide, there are some sentences that use these keywords in context.

You may wish to pause the next slide and read through them.

Here's the outline for today's lesson.

It's all about bunsen burner, so the first thing we're going to do is we're going to name some parts of a bunsen burner.

Then we're going to look at the flames.

Then we're going to look at how to light a splint safely and finally we're going to look at how to light a bunsen burner safely.

Let's get going with our first part, naming the parts of a bunsen burner.

A bunsen burner is used to heat things in science.

We're going to look at the different parts of the bunsen burner, what you can touch, what you can't touch, and the parts that you need to operate to change the colour of the flame.

So starting with the bottom, we've got the base.

The base is quite heavy.

This allows the bunsen burner to be very stable.

Only mean it won't tip over when you're operating it.

The next bit up from that is the gas connector.

The gas connector is where the gas comes into the bunsen burner and that's the fuel for the flame.

So that comes in through the rubber tubing.

The other end of the rubber tubing is attached to a gas tap.

Next we've got the collar and the air hole.

So the collar is cooled, so you don't need to worry about burning yourself when you're touching that collar.

You can close the collar and you can open the collar.

If you close the collar, that will reduce the amount of air that goes into the bunsen burner and you will get an orange flame.

If you open the collar, you will get more air into that bunsen burner and that will mix with the gas and produce a blue hotter flame.

We're gonna have a little look at that later on.

So the last bit is the chimney.

This does get hot, so you don't want to touch this when you're operating a bunsen burner.

This is the part the flame comes out the top of.

So we don't want to touch the chimney, because that will get hot.

I'm going to test you now.

So on which diagram is the collar circled? Pause the video now if you need some thinking time and then press play when you've written your answer.

If you said B, you're absolutely right.

Well done.

A is the chimney and C is the gas connector.

Here's task A for you, question one.

So this is a two part task.

I want you to label the diagram of the bunsen burner.

So you've got five parts to label.

Pause the video whilst you do this and then come back and press play when you're ready for the answers.

How did you get on? Okay, I hope.

So I want you to label this diagram of the bunsen burner.

We're gonna start at the bottom.

The bottom label is the base.

Then up from that we've got the gas connector.

Remember, that's where the gas goes in there.

We've got the collar, that's the cool part.

We can turn that, change the colour of the flame.

We've got the air hole next.

That can either be closed or open and finally we've got the chimney.

That's the part that gets hot and the flame comes out the top of it.

Well done if you've got all of your labels correct.

Part two now.

I want you to use the statements below to add descriptions to your labelled bunsen burner.

So I'm going to put five descriptions up and you are going to add these to the correct part of the bunsen burner.

So which part of the bunsen burner gets hot and flames come out of it? Which part of the bunsen burner does air enter? Which part of the bunsen burner is heavy to stop the bunsen burner from tipping over and which can be turned to change the colour of the flame? Where is rubber tubing connected to? What I want you to do now is pause the video, complete the task, and then press play when you're ready.

How did you get on? I hope this was fairly straightforward task for you.

So the base, that is the heavy bit that stops it from tipping over.

Next one up, gas connector.

That's where we connect the tubing to one end of the bunsen burner there and then the other end to the gas tap, the colour is the next one that can be turned.

Remember that doesn't get hot even when the bunsen burner is on.

The air hole, that's where air enters the bunsen burner to change the colour of the flame and finally the chimney.

That bit does get hot.

So you don't want to touch that when you're operating one.

Well done if you've got all of those correct, I think you're doing really well.

We've now completed naming and describing parts of a bunsen burner.

So now we're going to have a look at the different flames.

There are two main types of bunsen burner flame.

We've got the orange safety flame.

You can see that, definitely there.

You can definitely tell that that's lit.

You might have to look a little bit harder for the blue flame and you might want to think why is the orange flame called a safety flame? It's still hot at 900 to 1100 degrees C, compared to 1400 to 1600 degrees C.

So it is a bit cooler, but it's still very hot and it still could burn you.

So the orange flame is cooler, the blue flame is hotter.

Generally we use a blue flame for heating things up.

We don't use the orange safety flame very much.

However, what I would say is, and maybe you've noticed this already, if you're looking at the two flames, you can always see that orange flame, even in bright sunlight, you'll still be able to see the orange flame.

The good thing about that is that you won't accidentally put your hand into the orange flame when it's on.

Whereas the blue flame, if you leave it on the blue flame and you walk away, somebody else might not think that, that flame is on and come back, place their hand in it, pick up that bunsen burner and burn themselves.

So that is why we call the orange flame the safety flame just because we can see it, doesn't mean it's not hot.

To sum up the orange safety flame is easier to see in the lab.

However, if you heat something up with this, it will, it's called a dirty flame because little tiny bits of sot, are black and they will be deposited.

So you will see those on whatever you are heating.

So if you're heating up a test tube, that test tube would turn black if you heated it up in the orange flame, so it is cooler, but it's still hot enough to burn you.

The blue flame, particularly on a sunny day is difficult to see.

It's cleaner though, so it won't leave those black sooty deposits on your test tubes or your beakers when you're heating up with them and it is hotter.

If we want to change the colour of the flame, we just turn the collar.

It's important that you only touch the collar, because the chimney will be hot.

So if we turn it and we open up that air hole, you can see the flame goes from orange to blue.

When that air hole is open, it is a blue flame and when it's closed, it is an orange flame.

So it will change from that orange sooty flame.

Open it up, more air goes in to burn with the gas, and that will give a cleaner hotter blue flame.

Now let's see if you are listening, which part of a bunsen burner is turned to change the colour of the flame? Is it A, the collar, B, the gas connector, C, the chimney, or D, the air hole.

Pause the video if you need a little bit of time to think about this and press play when you've got your answer.

If you said collar, you're absolutely right.

Remember the collar doesn't get hot.

Now we're going to have a look at a check for understanding.

So what do you think about the following statements about the bunsen burner? I'm going to ask you for each statement, statement A, B, and C.

If you are sure that it's right, you think it's right, you think it's wrong or you're sure that it's wrong.

So statement A, flames are all the same temperature.

Statement B, you can touch some of the bunsen burners safely and it has one type of flame.

So I want you to write your answers.

So you might need to pause the video if you need a little bit more time to complete this task and then press play when you're finished.

Let's go through the answers.

Flames are all the same temperature.

No, that's incorrect.

There are two different flames.

The blue flame is the hotter flame, the orange flame is the cooler flame.

That orange flame is still hot enough to burn you though, so don't think that you can touch it.

You can touch some of the bunsen burners safely.

Yes you can.

You can touch the collar.

The collar will remain cool enough for you to turn it to change the colours of the flame and it does have more than one type of flame.

So it's got two types of flame.

It's got an orange flame and a blue flame.

So well done if you've got those all right.

Now I've got two true statements, so I want you to select two of these statements that are true.

The other one is false.

So find the true statements.

An orange flame is sooty, an orange flame is hotter than a blue flame, a blue flame is clean.

So which are the two true statements? Pause the video, have a think, answer it, and then come back and press play when you're ready.

So well done if you're selected that an orange flame is sooty and a blue flame is clean.

So although I've said that there are two main flames, an orange flame and a blue flame, there are actually three possible ways that we can have the flame depending on how we choose to set the bulls and burner up.

So here's a safety flame.

This is the gas tap open fully and the collar closed.

So this will give you an orange flame, like dirty flame.

So this is the orange safety flame.

Next way we could have something set up is we can have the collar fully open and the gas tap fully open and that is going to give us a blue roaring flame.

It's called a roaring flame, because it makes a kind of roaring noise when it's operating.

You can hear it.

Now the third kind of flame is, if you don't want to heat something really, really full on roaring flame, we can also use this type of flame.

So it's a smaller flame, it's the collars open.

Now we can adjust the gas tap so that it's partially open.

You can see that this gas tap is slightly turned off so there's less gas coming through and that's giving us a smaller, more gentle heating flame.

So we might choose to heat something up with that roaring flame.

When we've done the roaring flame and it's at temperature, if you want to heat it for maybe five minutes, we might choose to just adjust that gas tap, reduce the size of the flame and use that gentle heating flame.

So which one of these is incorrect? So we're looking for which is the wrong flame.

So we've got A with the collar open, B with the collar closed and C with the collar closed.

So which one of these is incorrect? Which one of these is wrong? Pause the video now if you need some thinking time and then press play when you're ready for the answer.

Well done if you said that B was incorrect, the collar is closed, so when the collar's closed, you would then get an orange flame like the one pictured in C.

So well done if you spotted that B was incorrect.

Now we're going to have a look at task B.

So this is an independent task.

Sophia has got some of the statements wrong.

She's trying to get a small blue, gentle heating flame and this is what she says.

You need to spot the errors and write the correct version of what she should do.

So she said "The blue flame is cooler and cleaner than the orange safety flame.

I need to have a closed gas tap.

I need to fully close the collar on the bunsen burner.

More air goes into the bunsen burner to turn it from a blue flame to an orange safety flame." So you need to look at those statements, find the errors and correct them.

What I want you to do is pause the video now, complete the task and then press play when you're ready to go through it.

How did you get on? Check your descriptions of a blue gentle heating flame.

Hopefully you've managed to help Sophia get it right.

So the blue flame is hotter and it's cleaner than the orange safety flame.

Remember the orange safety flame deposits soot.

So your words might not be exactly the same as Sophia's words, however it does still need to have the key concepts in each part.

So I need to have a partially open gas tap.

Remember she's trying to get that gentle heating flame, not the blue roaring flame, so she just needs it partially open, so part open.

She needs to open or fully open the collar on the bunsen burner, so that collar needs to be open to get that blue flame.

Just the gas tap needs to be reduced down a little bit and more air goes into the bunsen burner to turn it from a orange safety flame to a blue flame.

So what I'd like you to do is just check your descriptions.

Hopefully you've done really well so far.

Well done with your hard work so far.

We've named parts of and burner and match them up with some descriptions.

We've described how we can get three different flames.

Now we're going to look at how we could light a bunsen burner using a splint.

So the first thing we've got to do is learn how to use a splint safely.

So when we're using flames in the lab, here's what we need to be doing.

So whenever you're operating a bunsen burner, you've got some fire involved, here's what you've got to do.

You need to make sure that your bench is clear.

So that might mean that you need to tidy up, put your pencils and pens in a pencil case, put things away a little bit.

If you've got long enough hair to be tied back, then you need to tie that back, you should always bring a bubble to science lessons.

In order to do this.

All bags and coats should be outta the way.

Hopefully your lab's got somewhere for you to put these.

I know that my lab has got places for you to hang up your bags and coats and we make sure that all the floor is clear, so that we are not tripping over them and we've got flames in the way.

We need to stand up during practical work.

This can be an issue if you spill something.

If you stood up and you spill something, you can jump out of the way and you'll be okay and you should definitely wear some eye protection.

This might be safety glasses or it might be safety goggles.

You'd need to find out from your teacher which ones you would need to wear.

To light a bunsen burner in a science lab, you are going to need to use a splint.

It's long, it's thin and it's made of wood.

This allows us to transfer a flame from one bunsen burner to another to light it.

So it's important that we learn how to light a splint safely.

So the first thing you're going to do is you're going to hold the bottom end of the splint and you're going to place the top end of the splint in the orange bunsen burner flame.

Next thing you're going to make sure that, that splint is lit and then the splint is ready to use.

You're going to need to carry your lit splint across the classroom.

So here's what we need to know.

We need to carry it with the flame pointing a little bit downwards, shielded with the other hand and held away from the body.

This protects others from accidentally getting burned.

So here's a picture.

Now you don't want to have your hand too close to that flame because you might burn yourself, but if you don't put your hand there, you may accidentally set fire to somebody else and that would be a dangerous thing to do.

So it stops people from getting accidentally burned.

So if you notice you've got a little bit of an angle, so the splint is pointing downwards, you will need to do this and you will need to practise.

So we said that we needed to carry that splint across a classroom.

Obviously this has potential hazards such as setting fire to things or burning other people accidentally.

So first of all, you need to hold it to the correct angle.

So this angle here is about what you need to have at, slightly downwards to allow the flame to travel at a, and burn it a sensible rate.

If it burns too quickly, it's going to burn your hand.

If it burns too slowly, it might go out.

So if you hold it too vertical, so the flame's at the bottom and you hold it too upwards, it's going to burn too quickly and that flame can quickly travel along that splint and if it's too vertical so the flame's at the top, the flame can go out.

So it's important that you practise how to carry this splint across the classroom.

Just a quick check for understanding, what is the correct angle that you must carry a lit splint.

Is it A, B, or C? Pause the video and now to give you some thinking time, and press play when you're ready to come back.

If you said B, well done, this is about the correct angle.

A, would burn out and perhaps go out completely before you got to light your bunsen burner and C, may burn too quickly and burn your hand.

Take a look at the splint being blown out.

You can see that there are some embers still left.

These are dangerous and so we would not recommend that you blow out a splint this way.

Instead, what you need to do is you need to rub it backwards and forwards on a heat resistant mat and that will extinguish the flame safely.

Here's task C.

Laura's looking for some advice about what to do and not do when you using a lip splint.

So what I want you to do is sort the statements into a do and a do not list.

So the first one's been done for you.

So here's our list, a do and a do not.

So do shield the flame with the hand.

Do not hold it vertical with the flame at the top.

Here are the statements that you need to sort in a do and do not list.

So sit down when using flames, tie hair back, put out the splint by rubbing on a heat resistant mat, hold vertical with the flame at the bottom, hold at a slight downward angle, blow out the splint.

I want you to look at each one of these statements and put them in either the do list, which is things that you should do to use a splint safely or the do not list, which is things that you should not do, because they're not safe to do so.

Pause the video now, complete the task and then come back when you're ready for the answers.

How did you get on? Hopefully you've got your lists complete of what to do and what not to do.

So tie hair back, definitely tie your hair back.

It's a basic safety precaution that you should take.

Do not sit down when using flames.

Hold at a slight downwards horizontal angle.

So you want to hold it at the right angle that allows a splint to burn correctly, at the correct rate.

You don't want it to burn too fast, you don't want it to go out.

So you don't wanna hold it vertical with the flame at the bottom because that means that the flame will burn too fast and may potentially burn your hand.

You want to put the splint out by rubbing on a heat resistant mat.

You don't want to blow out the splint, 'cause you don't want those glowing embers to go anywhere.

Well done if you've got all those right.

We're now going to get onto the final part of the lesson.

We've named parts of bunsen burner.

We've looked at the different flames.

We've looked at using a splint and now we're going to look at lighting a bunsen burner safely.

So here are some safety considerations before lighting the bunsen burner.

We're obviously gonna be wearing some eye protection goggles or glasses.

Your teacher will tell you which ones you need to wear.

You're going to be tying your hair back, stand up and use a heat resistant mat for you on some burner.

You also need to check the rubber tubing visually for split or damages.

So this can happen quite often.

Some of the bunsen burners and the tubing have been in the lab and maybe perhaps not used for a little while.

So you need to, each time you do it, you need to check the rubber tubing.

So this is really old damaged rubber tubing.

You can see the cracks and the splits in this and this is really safe rubber tubing.

There's no splits, no damage.

What you need to do is each time you use a bunsen burner, just visually check that bunsen burner tubing.

Make sure there's no cracks or splits or damage.

We don't want the gas to escape, 'cause that might be dangerous.

So to like a bunsen burner in a science lab, you need to check that the collar is in the closed position and the gas tap's off.

Use the nearest bunsen burner to light the end of a splint.

Walk, don't run, don't walk really fast.

You just need to get your bunsen burner lit and you need to take that splint safely from the nearest lit bunsen burner to yours.

Then you're going to get your partner to turn the gas tap on when you arrive with a lit splint, don't do it before because the gas will start to fill the room whilst you're away getting a lit splint and that can cause issues with a bigger flame than you would like when you get back and light it, so your partner only turns on the gas tap when you arrive with a lit splint and finally, just place a lit splint near the chimney.

You want to do this at an arm's length and don't look over the top of it when you're doing it, 'cause you don't want the flame to accidentally burn any of your hair.

So the bunsen burner should now be lit.

Okay, so here's a demonstration.

Turn the gas tap on, lit splint, top of the chimney and it's lit, brilliant, ready to go.

So gas tap on, here comes the lit splint, touch it to the top of the chimney and then place it on the mat and put it out.

Well done.

You've got a lit bunsen.

Well done for working hard this lesson.

For this final task, we're going to write a five step method for lighting a bunsen burner safely.

Each one of these images is a different step, so you should number the steps one, two, three, four, and five, and just describe what you're seeing in each one of these images.

Pause the video now complete the task and then press play when you're ready.

Well done for completing the final task of the lesson, lighting a bunsen burner safely.

So you might have included some of these safety considerations.

So wearing eye protection, checking the bunsen burner tubing, tying your hair back, use a heat resistant mat and stand up.

What we're going to do is we're now going to mark each one of these.

So your answers should be similar.

It might not be word for word, 'cause you might have used separate words, but you certainly need to include each one of these five steps.

So first of all, you're going to check the collar is closed and the gas tap's off, then you're going to use the nearest lit bunsen burner.

We're not gonna walk right the way across the classroom.

We're gonna use the nearest lit bunsen burner to light the end of the splint.

Then you're going to walk at a safe speed to your unlit bunsen burner.

You're going to get your partner to turn the gas tap on, and finally place your splint near the chimney and your bunsen should now be lit.

Well done if you've got these all correct.

Here's a summary for today's lesson.

Well done for working hard and following along.

The heavy base of a bunsen burner does not get hot.

Opening the air hole of a bunsen burner changes from a yellow and sooty flame to a hotter, clean, and blue flame.

The gas tap can be turned to make the flame of a bunsen burner smaller or bigger.

The splint used to light a bunsen burner should be lit from the nearest bunsen burner that is already on.

A lit splint should be carried with the flame pointing downwards a little and shielded with the other hand.

Well done for working really hard this lesson.

You've done great.

You've worked so hard on learning how to light a splint, label and describe a bunsen burner and light, a bunsen burner, safely.