Two gases from water.
Why does water electrolysis make twice as much hydrogen?
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Why does water electrolysis make twice as much hydrogen?
Why does water electrolysis make twice as much hydrogen?
Fit electrodes, electrolyte cell and separate collectors
The external supply drives a nonspontaneous reaction. Two electrons form one hydrogen molecule at the cathode, while four electrons produce one oxygen molecule at the anode.
Conducting water with inert electrodes; 1.8 V illustrative activation/overpotential and 5 Ω cell resistance. 100% Faradaic efficiency, 24 L/mol gas volume, no gas recombination. This is a schematic calculation, not an experiment instruction. Liquid is shown by level, wave and meniscus strokes so immersed hardware remains visible in the cutaway.
Collect at least 5 mL hydrogen with twice the oxygen volume.
Compare hydrogen and oxygen volumes from electrolysis.