Gas, gas, gas, gas, gas, gas. Welcome to Business Daily and our latest delve into the world of chemistry as we break down the world economy element by element. And this week, we're looking at a yellow gas that is one of the most ferocious and frightening members of the periodic table.

If you smell fluorine, what you do is you run away, as fast as you can.

But it is the other gases that can be made with this chemical element

that pose the real threats to mankind.

Everything from global warming to the risk of being fried by the sun.

They have lifetimes in the atmosphere ranging to thousands of years. Yep, that's right.

This week we are looking at fluorine. Right, so we've come as usual to the laboratory of Professor

Andrea Sala. So, Andrea, show me some florey. I'm sorry. We haven't got any elemental, pure fluorine.

And the reason is because fluorine is actually the Tyrannosaurus rex of the periodic table.

I mean, this is a tiger that basically reacts with every element apart from helium.

And so this is actually something we just don't routinely keep in the lab.

Tell me, if you had some, what would it look like?

What is it?

Well, fluorine is a gas.

It's got a pale yellow color.

And apparently it's got a smell a little bit like chlorine.

You say apparently because clearly you've never smelt it.

I have smelt what comes out of a cylinder.

And the thing is that you don't actually smell the fluorine. What you smell is the product of its reaction with oxygen.

But generally, if you smell fluorine, what you do is you run away as fast as you can.

Okay, so fluorine is incredibly reactive, but if it's reactive, it reacts with substances

to create materials which presumably are more stable.

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