Question:
I have seen vague descriptions of demonstrations in which bottled
hydrogen and oxygen are used to blow free floating soap bubbles, which
can then be ignited.
Is there a simple set up which can be used to fill soap bubbles with
hydrogen and oxygen gas generated directly from electrolysis?
I found that sticking my electrodes in soapy salt water just generates
a lot of dense tiny bubbles, which don't ignite.
Running the gasses through a tube dipped in a bit of soap works OK,
but the bubbles tend not to be released from the tube, and they pop
before they become free floating. For safety reasons, I don't care to
ignite soap bubbles while they are still attached to a tube which is
attached to my electrolysis glassware (well, OK, I tried it once with
predictably unsafe results).
Bottom line: What does it take to get soap bubbles to release from a
tube before they pop?
Answer:
-Not a hobby, really. Trying to set it up as a classroom demo. I have
the necessary safety shield and all that.
What I'd eventually like to do is hook the electrolysis apparatus up
to a hand crank power generator, to demonstrate transformation of
energy. From mechanical energy (hand crank) to electrical energy, to
chemical potential energy, to heat and sound energy. I've already
been successful running the electrolysis with a hand crank. It's just
that last energy transformation I need to optimize.
You're right about inverting gravity (or at least inverting the hose
that the bubbles are emerging from). I'll try that later today. -Run the gas from the electrolyser through a 1/2" or bigger tube and into
the soap solution. Might have to jig about the conc. of the soap - I
just use dishwashing liquid with a bit of glycerol. Works fine. I don't
use an electrolysis setup for this demo, just a Buchner flask with a
stopper, aluminium foil and NaOH solution. No cogeneration of oxygen
that way.
