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- Homework Statement
- Find the required energy and volt needed for electrolysis of water

- Relevant Equations
- Coulomb's law: F = k * q_1 * q_2 / r*r

V = W / q

Hello everyone,

I'm just doing a bit of review of math to be used in electrolysis calculations. From the reference:

https://www.ccmr.cornell.edu/wp-con...o_Skyler_splitting-water-with-electricity.pdf

the result for r12 on page 4, the author has 1.5 * 10e-11 m. Google sheets and MS Excel has 1.89e-10 = sin(52) * 2 * 9.6e-11.

Also, for U12 using my result of r12 instead of the author's, I got 1.28e-19 instead of the author's 1.6e-19. If I used the author's result for r12, I got 1.62e-18.

And the covalent bond energy of H-O = 464 kJ / mol to break the bond from:

https://opentextbc.ca/chemistry/chapter/7-5-strengths-of-ionic-and-covalent-bonds/

The total U from 'splitting water with electricity' is too low 8.54e-19 J (author's) or 8.86e-19 J (based upon my results of r12) from the covalent bond energy above (464 + 464) * 1000 / 6.022e-23 = 1.54e-18 J.

Would someone please check if my findings are correct? Does anyone know where I can get a more accurate than the above for covalent bond energy reference?

Thanks,

Tommy

[Edit] PS: If I use the complete calculation for covalent bond energies for the electrolysis reaction:

2 H-O-H => 2 H-H + O-O

( 2(464 * 2) - (2 * 436) - 140 ) * 1000 / 6.022e23 = 1.4e-18 J

But to get the net energy required for 1 molecule of water, 1.4-18 J / 2 = 7e-19 J.

Which still doesn't equate to electrostatic force result.

I'm just doing a bit of review of math to be used in electrolysis calculations. From the reference:

https://www.ccmr.cornell.edu/wp-con...o_Skyler_splitting-water-with-electricity.pdf

the result for r12 on page 4, the author has 1.5 * 10e-11 m. Google sheets and MS Excel has 1.89e-10 = sin(52) * 2 * 9.6e-11.

Also, for U12 using my result of r12 instead of the author's, I got 1.28e-19 instead of the author's 1.6e-19. If I used the author's result for r12, I got 1.62e-18.

And the covalent bond energy of H-O = 464 kJ / mol to break the bond from:

https://opentextbc.ca/chemistry/chapter/7-5-strengths-of-ionic-and-covalent-bonds/

The total U from 'splitting water with electricity' is too low 8.54e-19 J (author's) or 8.86e-19 J (based upon my results of r12) from the covalent bond energy above (464 + 464) * 1000 / 6.022e-23 = 1.54e-18 J.

Would someone please check if my findings are correct? Does anyone know where I can get a more accurate than the above for covalent bond energy reference?

Thanks,

Tommy

[Edit] PS: If I use the complete calculation for covalent bond energies for the electrolysis reaction:

2 H-O-H => 2 H-H + O-O

( 2(464 * 2) - (2 * 436) - 140 ) * 1000 / 6.022e23 = 1.4e-18 J

But to get the net energy required for 1 molecule of water, 1.4-18 J / 2 = 7e-19 J.

Which still doesn't equate to electrostatic force result.

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