This work was created by Dr Jamie Love and licensed under a Creative Commons Attribution-ShareAlike 4.0 International License.

All right! My first "Do This!" Are we going to smash atoms together and transmute elements?

No. Afraid not. Unfortunately, I cannot think of a simple experiment you could do that connects to the subjects we've talked about. You need sophisticated, powerful machines from the 20th or 21st century to do nuclear chemistry.

Not really. Radioisotopes are not that easy to find in nature. Besides, radioactive isotopes are the last "hands on" experiment I'd want to do! Safety becomes an issue.

"Boring" things like safety have kept me alive and well for thousands of years. And it is important that you keep safety in mind whenever you do a "Do This!". Or, for that matter, whenever you do anything!

Whether you do your Alchemy in a lab or in a kitchen, safety should always be at the front of your mind. For an Alchemist the biggest safety hazards are fire and "nasty" chemicals.

True, but fire is not, as the Ancients believed, an element. Fire is a chemical reaction, and once started it will continue to burn until it runs out of an important ingredient. The trick to fire safety is to make sure you don't start a fire you don't want. We will discuss FIRE in great detail in the last Element of Principles of Alchemy.

OK. A brief explanation of fire is appropriate at this time.
Fire needs fuel to burn. That fuel can be a gas (like from a stove), a liquid (like the stuff that runs oil lamps) or a solid (a piece of wood, or you!).
Fire also needs air. Specifically, the oxygen in air.
You can stop any fire if you can separate the fuel from the oxygen. Smother the fuel and you stop it from burning.

Water is a great way to stop most kinds of fire. But NOT grease fires!

Grease floats on water so water can't put out a grease fire. In fact, it usually makes things worse!

If you pour water on a grease fire the water causes the grease and fire to splash and sputter. It's a dangerous thing to do. So NEVER try to put out a grease fire by dumping water on it.

Good.

Dumping water on a fire covers the fuel, thus keeping the oxygen away. (Unless the fuel floats on water, like grease and oil can.)

That's right. Water smothers the flame. There are other ways to smother a flame.

Well, in the future they have marvelous devices called fire extinguishers. They are very good against grease fires. Most fire extinguishers work by producing a huge amount of carbon dioxide. This is "bad air" that will kill a fire, or you, if you get too much of it.

Well, it isn't quite that simple. You use the fire extinguisher by directing the carbon dioxide gas at the foot of the flame, not at the top. That's because the fire (chemical reaction) occurs at the base of the flame where the fuel and oxygen meet. The top of a flame tends to draw our attention, but the bottom of the flame is where all the action is! Anyone trained in fire safety knows to point the extinguisher, or hose at the floor of the flame.

When you have no water or carbon dioxide extinguishers at hand, earth can be used to smother the flame. Sand dumped onto a flame will cut off the supply of oxygen and kill the flame.

Well, that's much better than a fire!

Why, yes. I hadn't through of it that way.

Well, that is an entertaining idea but not a completely accurate one.
You give off a tiny bit of carbon dioxide, but not enough to smother the flame. And if you blow gently you can even help a flame to burn brighter!

Because the candle flame is small and you can blow a lot of air!
The three methods we discussed for extinguishing a flame (Water, Earth and "bad" Air) all smother the fuel, and thus keep the oxygen out. But blowing out a flame doesn't smother it. Instead you are stripping the fire away from its fuel.

Fire makes more fire by continuing to the burn the fuel. Fire needs fire to continue burning.

OK. As a fire burns in a particular spot, it runs out of fuel. But the heat it gives off is enough to cause the fuel nearby to ignite.

Right. So a fire must constantly search out more fuel to burn if it is to be kept alive.

So, when you blow hard on a candle flame you are using your breath to push the hot flame away from the fuel. Remove the heat from the fuel and you've stopped the reaction.

That's right. A bigger flame requires a bigger push of air from you to push it away from the fuel.

Right! The bigger the flame the more air you need to push quickly at it in order to push the fire away from the fuel. In the 20th century they have some fire accidents involving very good fuels that produce very big fires. To put out these "super-fires", they must use explosives to blow the flame away from the fuel.

Yes. When you blow gently on a small flame you push a fresh supply of oxygen to it. And you might even help the flame reach new fuel that would normally be out of reach.

Yes. It depends on the size of the fire and how hard you blow. I've seen people try to swat down a fire with a coat or apron. If the fire is small enough and they swat it correctly, they put out the fire. But sometimes they make it worse! They fan the flames, adding more oxygen and making the fire grow.

Yes. If not before! Tell me, Arthur. What do you do if the flame is so big you can't blow it out, and you don't have anything to help you put it out?

Yes! Exactly. A fire out of control is a dangerous thing and requires professional fire fighters right away! Some fires get out of control because people think they can handle it on their own. They waste valuable time and put themselves in danger. Always put safety first - your safety, and anyone else's. And never let a fire block your exit. Be sure you can escape if you need to.

And don't hang around fighting a fire that is filling the room full of smoke. Most fire deaths are due to the smoke not the flames. People can be overcome by smoke and fumes.

That's right. If in doubt, get out! Get the fire experts and stay out of the house until the fire folks tell you it is safe.
Now you know how a fire works and how to put one out (or get help). But the best form of fire safety is fire prevention.

Well, there's a series of "Never Do This!" rules that you should always keep in mind.

NEVER strike a match near a flammable substance. A flammable substance is anything that will catch fire. Some flammable things will burn very slowly while others will go up in an explosion! Without knowing exactly what the substance is, it's hard to say what will happen. Therefore, whenever you see the word "flammable", consider it to be a potential "bomb" and don't let a fire near it.

NEVER point a lighter at yourself, or anyone else, and then light it.

Oh, it's a 20th century fire making tool full of a flammable substance under pressure. When you light it, a flame shoots out.

Yes.

NEVER be fooled by "dead flames". Matches, cigarettes, etc. may appear to be out but they may still have a hidden bit of flame in them. We say they "smolder". When something smolders it burns very slowly, often without smoke. But there's still a fire inside and all it needs is more fuel or air to be awakened.

The only way to be sure a fire is not smoldering inside an object is to open it up and look. But that can be dangerous! Usually we are not interested in whether or not it is smoldering. We just want to make sure it won't smolder any more. The best way to dispose of a match, or anything else which has recently been on fire, is to sink it in water. The next best way is to crush the match (under foot). This breaks up the "insides" and exposes the material so there's no place for a small flame to hide. Also, crushing smothers the fuel and kills any remaining flame.

Right. That way you can be sure nothing will re-ignite.

Smother the flame as fast as possible!
If there's a lot of water within reach, like a sink or hose, then dump water on it. Quickly.
Otherwise shout for help and fall to the floor. Roll over on the flame to put it out. If there's time, you might try to wrap a heavy towel or a bit of carpet around the flames to try to smother them.

It is. I've seen the results of fire accidents and don't want it to ever happen to anyone. So when you are around a flame, making a flame or extinguishing a flame, be sure you know what you are doing.

As in all emergencies the first rule is "don't panic".
If the fire is too large to fight (and don't be brave about it), shout for help and leave the room immediately. If you can, close the door of the room where the fire is burning and close all other doors behind you. Do you know why?

Right. Very good! (Of course, don't lock someone inside behind you!)
Make your way as quickly as possible out of the house. Before you open any closed door (in a burning house), first touch it or the door knob with your hand. If it's warm there's a fire on the other side.

That's right. It is a good idea to plan escape routes from your house so you can get yourself out of the house as quickly and safely as possible. Don't wait until a fire starts! Plan ahead.

Right. Call the fire brigade yourself or get a neighbor to call. And NEVER go back into your house until a fire officer has told you it is safe.

Close the door(s) nearest the fire and use blankets or towels to block gaps between the door and frame to stop the smoke.

Yes. Temporarily. If the room becomes smoky, crawl on the floor.

Because the hot smoke rises upwards. Make your way to a window and try to attract some attention.
That shouldn't be hard for you.

What!? Why you little....

Oh. Ah. If you are in immediate danger, drop some cushions out the window to provide something soft to aim for. Then climb out the window, feet first, and lower yourself by your hands until you are stretched to full length. Then drop to the ground, trying to hit the cushions and rolling with the fall.

Ah, well, yes, that's a good idea. If you have a safe way to climb down then by all means use it.
Understand?

Aye! As long as you pay attention to what you are doing and use some common sense, you should have no trouble with fire. Prevention is the key. Think before you strike a match.

Yes. Hazardous chemicals. Some chemicals are dangerous. A lot depends on their concentration and how you are exposed to them.

Ah, probably eating or drinking it. Anything that could put a dangerous chemical into your body is hazardous. With some dangerous chemicals, a small whiff won't kill you, but if you were to eat or drink it, or even get it on your skin, you could be poisoned.

Yes, it would. But it is much easier to read labels.

Yes. Chemicals come in containers and the dangerous chemicals have warnings on the container telling you what is dangerous about it. Read the label, and be sure you understand it before you do anything with that chemical. If it is dangerous, the label will say so, and it will tell you what to do if you have accident.

Yes, "follow directions" is always good advice.
The chemicals we will use in this course are common and very safe when used correctly.

Use common sense. If you don't know what it is don't eat it, don't drink it and don't get it on yourself.
And don't touch a flame to it.

Yes, that's it. I could go on and on about fire and chemical safety, but the bottom line is be sure you know what you are doing and pay attention to what you do.

Well, I wanted to cover safety today because in other "Do this" lessons we will use small flames and stoves. And we will use a few household chemicals too.

Well, I survived the "Principles of AIR" and I we didn't even do a "hands on" experiment. You always say one should get involved with the science. But here you've gone and dragged me through a complete Element without one demonstration that you are talking about anything real or useful.

OK. OK. Let me think a wee bit....
Right. How about a demonstration that would have confounded the brightest minds of our time (the 5th century)?

We'll prove that air has mass. And we'll build a simple balance in the process.
So, "Do this"!

Get a long, thin piece of wood (2 feet long, or so). Use a ruler to find the center and mark it with a pencil.

Push a tack into each side of the wood at the center. They will act as a pivot for the balance.

I don't have any tacks.

Use drawing pins or anything that will give you a pair of "nubs" sticking out from the wood's center. Then make a loop of string and fix it around the pins. You could use a large rubber band.

What kind of band?

Never mind. Just use some of my 20th century supplies. Now, when you lift the wood up, using the loop, it should balance.

Yes. Exactly. If it isn't level, tape a coin or small bit of something on the higher end of the stick to make it balanced. It should be flat and level.

OK.

Now, tape a balloon at each end of the wood. And check again to see that the wood is still balanced. Be sure you have two balloons of the same size. You can move one balloon along the length if the wood is not balanced.

Right. It's balanced. Now what?

Remove one balloon (but mark where you had it taped to the wood) and blow it up. Then tie it closed and tape it back where it was. Now check the balance and explain the results.

This work was created by Dr Jamie Love and licensed under a Creative Commons Attribution-ShareAlike 4.0 International License.