Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

What amount of amperage do i need for electrolysis of water?

  1. Nov 16, 2016 #1
    ok i want to make 1g/sec of hydrogen out of an unlimited supply of water, i know the electrolysis wont start below 1.48 volts, let suppose i am supplying 2 volts of DC current, i need to find out the total wattage for electrolysis, for this i need the amount of current required to produce 1 g/sec of hydrogen
     
    Last edited: Nov 16, 2016
  2. jcsd
  3. Nov 16, 2016 #2

    phinds

    User Avatar
    Gold Member
    2016 Award

    "2V" is NOT "DC current". It is potential, not current at all. Do you understand Ohm's Law?

    Have you done any research on this? If so, what have you found? If not, then go do some.
     
  4. Nov 16, 2016 #3
    Ok ok i have mistaken its i am applying a potential of 2 volts and i need to find out the amount of current can you guide me please? i am very weak in electrical stuff
     
  5. Nov 16, 2016 #4

    phinds

    User Avatar
    Gold Member
    2016 Award

    You are asking completely the wrong question. You can't specify the amount of current, you have to specify the voltage and then the current will follow from the amount of resistance over which the voltage is applied.

    AGAIN, I say, do some research.
     
  6. Nov 16, 2016 #5

    Bystander

    User Avatar
    Science Advisor
    Homework Helper
    Gold Member
    2016 Award

  7. Nov 16, 2016 #6
    Bystander? sir i used faraday but its giving me an answer of a very large amount of current
     
  8. Nov 16, 2016 #7

    Bystander

    User Avatar
    Science Advisor
    Homework Helper
    Gold Member
    2016 Award

  9. Nov 16, 2016 #8
    Have you figured out how much hydrogen 1 gram is?
    have you figured out how many water molecules must be split to get that much H2
    What about the surface area and material of the electrodes
    Have you defined the concentration of the electrolyte.

    It world be far easier to figure it out experimentally but you still need to convert 1g of H2 to a volume at a certain pressure or its going to be hard to measure
     
  10. Nov 17, 2016 #9
    Please check my calculations:
    The half reaction at cathode ;
    4e + 4H2O ------> 2H2 +4OH
    this means 1 mole of electron can produce 0.5 mole of Hydrogen gas. now
    for example i want to produce 1 gm of h2/sec this means 3600gms in 1 hour
    so no of moles is = mass of H2 required/molar mass of H2
    so no of moles = 3600/2.02 = 1782.17 moles of H2
    Now as i know that 1 mole of electron gives half mole of Hydrogen i need double amount of moles of electrons to get 1 mole of hydrogen
    so no of moles of electron = no of moles of H2 x 2
    no of moles of electron = 2*1782.17 = 3564.35 moles of electron
    as i know that 1 mole of e = 1 F so 3564.35 moles of electron means 3564.35 F
    to obtain the charge in columb
    3564.35*96485 = 3.44*10^8 columb
    now current is I = (3.44*10^8C)/3600s
    I = 95529 Amps
    WTHH! whats wrong here
     
  11. Nov 17, 2016 #10

    Bystander

    User Avatar
    Science Advisor
    Homework Helper
    Gold Member
    2016 Award

    Nothing, read the linked article on electrolysis.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted