Faraday's First Law

[turtlebanana]

In the textbook, it states that ''an electroplating cell can be used to study the relationship between the mass of the metal formed at the cathode and the quantity of charge that passes through the cell''.

The ''mass of the metal formed at the cathode'' can be directly determined by weighing the cathode. However, the ''quantity of charge that passes through the cell'' is determined indirectly via the formula:
charge (coloumbs) = current (amps) x time (seconds) or  Q = I x t.

But what exactly does the quantity of charge that passes through the cell mean? What exactly is Q and how does it differ from the current that passes through the cell? Does the charge (Q) refer to the charge of the ion?

[sweetcheeks]

The charge that passes through the cell is related to the number of electrons that is being passed through the cell. Faraday's constant (96500 C) is the charge, in Coloumbs, that one mole of electrons carries. Therefore, if Q was to equal 96500, it would mean that 1 mole of electrons has been passed through the circuit.

Current refers to how many electrons pass a certain point in 1 second (technically it is measured as rate of flow of electric charge, but for high school chemistry it can be looked at as the rate of electron flow). Q looks at the total charge that has passed through that point, rather than just for one second. So Q looks at the total number of electrons that has passed in a circuit (which is why it is current x time).