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  • Okay, Neil is repeating an experiment which is quite a famous one where you take a lighted methane oxygen torch and plunge it into soapy water.

  • So, of course, when you put it in, it cools down on the flame goes out, so you blow bubbles on.

  • The bubbles contain a mixture of oxygen and methane, a potentially explosive mixture on when you put a flame to it, it goes off with an enormous bang.

  • I'm very rapidly.

  • Fortunately, I wasn't there or my ears would still be ringing.

  • We've already so new videos of soap bubbles that just contain methane, and if you like those, they burn really quite gently and in a controlled way.

  • In fact, Sam Tang has done it on her hands.

  • The heat is not enough really to damage now, when you do it with oxygen and methane, the amount of heat to liberate is exactly the same methane plus oxygen, but it liberates the heat very rapidly, so you get a big pulse of heat rather than this gentle burning that you see in Sam's pimples.

  • But me Thane is not mixed with the air on dhe, so it takes time for the oxygen from the air to diffuse into the gas, okay, and so it burns relatively slowly.

  • Oh, nothing seems in the case of Neil's bubbles.

  • First of all, we using pure oxygen.

  • There's no nitrogen from the air, and the methane and the oxygen are mixed in just the right ratio to burn really well.

  • And they mixed at a molecular level.

  • So once the reaction starts, it could go really rapidly, and it's not limited by the rate at which the gases mix.

  • So this is pre made for destruction, and so you get a very rapid explosion.

  • It goes so fast that even our slow motion camera doesn't see very much.

  • So the take home message from all of this is that if you have your chemicals properly mixed in this case meeting oxygen, the reactions can go very much faster.

  • If you want an analogy, it's like eating spicy food.

  • If you have the chilli sauce on one side and gently dip in your food, there's a gentle warming up.

  • If it's all mixed in together, the first mouthful is fouled.

  • So what I thought we do is investigate today an explosive mixture of methane and hey and to do that.

  • We're gonna use this very crude device.

  • It's just simply can no.

  • Me and Neil have doctored it slightly by drilling a couple of holes.

  • Okay, One in the bottom and one in the top.

Okay, Neil is repeating an experiment which is quite a famous one where you take a lighted methane oxygen torch and plunge it into soapy water.

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