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What is a candle flame really made of?
I am at the Palace of Discovery in Paris to do an experiment
that beautifully demonstrates the answers.
Ok so we're turning on an electric field here
and we see that the flame is spreading out.
Thats very cute,
it's like a butterfly.
And you can see that the flame
has two separate pieces to it now.
One is going towards the negative plate.
Those would be the positive ions,
and the negative ions will be going towards a positively charged plate.
So we see the flame kinda flattening out.
But if that didn't convince you
that flame contains ions,
then check part two of our experiment
where we compare the conductivity of a
flame to the connectivity of air,
which is normally a pretty good insulator.
It requires about 10,000 volts
to break down a centimeter of air.
So right now this plate is is about 20,000 V.
You see that the spark is only little,
but if I put it around the flame,
we will see if we can get a bigger spark happen.
Look at that, yeaaa!
Because the flame has those ions in it,
that means that we can break down
a greater distance of air.
This greater conductivity.
It's awesome! You love doing this, right?
A strong enough electric field
can actually extinguish the flame
but watch carefully what happens when the flame goes out.
Just like in the flame, the opposite charges in the smoke
are pulled in opposite directions.
Now while some may argue that a flame is not
truly a plasma because it's not hot enough
and it doesn't have a high enough density of ions,
one thing is for sure, it does contain ions
which have important electrical properties,
which can be demonstrated if you have a strong enough electric field.