Question dealing with electrolysis and laser calculation. tia sal2

Greetings All

I have a question dealing with electrolysis and lasers the text books
say you need 1.25 electron-volts (eV) or 2.002 x 10 - 19 Joules to do
electrolysis with water. A small pen laser puts out about 5mW which is
about .005 Joules. Why can't small pen lasers do electrolysis? Are my
calculations incorrect or am I not taking into some other factor.

Thanks
sal2
 
D

Don Klipstein

Jan 1, 1970
0
Greetings All

I have a question dealing with electrolysis and lasers the text books
say you need 1.25 electron-volts (eV) or 2.002 x 10 - 19 Joules to do
electrolysis with water.

That sounds to me like the work needed to electrolyze one water
molecule. Or maybe the work per electron, and two electrons have to flow
to electrolyze a water molecule, so you may need twice that much to
electrolyze one water molecule.
A small pen laser puts out about 5mW which is about .005 Joules.

That's .005 joule per second.
Why can't small pen lasers do electrolysis? Are my
calculations incorrect or am I not taking into some other factor.

I would say both. For one thing, water molecules don't do much
absorbing of laser pointer light. And if you use a wavelength that water
molecules do absorb, you just heat the water.

- Don Klipstein ([email protected])
 
J

Jasen Betts

Jan 1, 1970
0
Greetings All

I have a question dealing with electrolysis and lasers the text books
say you need 1.25 electron-volts (eV) or 2.002 x 10 - 19 Joules to do
electrolysis with water.
yes.

A small pen laser puts out about 5mW which is about .005 Joules.

no it isn't




Bye.
Jasen
 
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