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How does electrolysis work?

  1. Sep 14, 2013 #1
    Right, I've started physics a level and electrolysis has always confused me since gcse, so please be very detailed!
    This is what I know, (or assume) so far: there is a cell; that cell is connected to two electrodes; one is positive, the other is negative. The electrodes are placed in an ionic solution, where positive ions move to the negative electrode and negative ions move to the positive electrode.
    I don't understand how current moves throughout the process. How do the electrodes get their charges in the first place? And overall, what direction does the current flow if the ions in the solution move in both directions!
    Please help me!
  2. jcsd
  3. Sep 14, 2013 #2
    You attach the electrodes to a battery which makes one negative and one positive. An electric field will be produced between the two electrodes, and charges in an electric field experience an electric force. The positive and negative ions experience forces in the opposite direction.

    The current takes the sign of the charge as well as its direction into account. A positive charge moving right to left gives the same current as a negative charge moving left to right. When the positive and negative ions move in opposite directions, they both add constructively to the total current.

    1 amp of negative charge moving one direction + 1 amp of positive charge going the opposite direction = 2 amps total.

    Whichever way you define this total current is a matter of convention, and I've forgotten which way humans conventionally decided on.
  4. Sep 14, 2013 #3


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    A battery is connected to two electrodes put into a solution.The positive electrode is in the side of positive terminal of battery and vise versa.(Because the electrons in the Anode(Positive electrode) moves towards the positive terminal of battery making the electrode positively charges and vise versa).The cations move toward the cathode(negative electrode) and gets discharged,so,gaining electrons.The Anions(negative ions)moves toward the anode(positive electrode)giving electrons to the positive electrode which travels to the positive terminal,thus electrons flow through the circuit.
  5. Sep 15, 2013 #4
    Thank you, i understand the process more now
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