Calculate the amount of copper deposited in a zinc/Copper electrode of electrolytic cell when 2.5A of electric current is passed in 10 minutes?
1A = 1C/s
so, how many electrons in 600 seconds?
How many electrons per molecule deposited?
Now you can figure the # molecules, and thus the # moles, and thus the mass
To calculate the amount of copper deposited, you need to use Faraday's law of electrolysis, which states:
Amount of substance deposited = (Electric current x time) / (Faraday's constant x number of electrons transferred)
1. Determine the number of electrons transferred in the reaction.
In this case, copper ions (Cu²⁺) are being reduced to form copper metal (Cu⁰). The reduction half-reaction can be written as:
Cu²⁺ + 2e⁻ → Cu⁰
From the equation, we can see that 2 electrons are transferred per copper ion.
2. Calculate the amount of substance deposited (copper) using Faraday's law.
Faraday's constant (F) is the charge of 1 mole of electrons and is equal to 96,485 C/mol.
Amount of copper deposited = (Electric current x time) / (Faraday's constant x number of electrons transferred)
Plugging in the values:
Electric current = 2.5 A
Time = 10 minutes = 600 seconds
Number of electrons transferred = 2
Amount of copper deposited = (2.5 A x 600 s) / (96,485 C/mol x 2)
3. Convert the amount of copper deposited to the desired unit (grams).
To convert from moles to grams, you need the molar mass of copper (Cu), which is approximately 63.55 g/mol.
Amount of copper deposited (in moles) = Amount of copper deposited (in grams) / Molar mass of copper
Amount of copper deposited (in grams) = Amount of copper deposited (in moles) x Molar mass of copper
Substituting the values:
Molar mass of copper = 63.55 g/mol
Finally, calculate the amount of copper deposited.