When 1 mole of Cu2+(aq) is reduced to Cu (s), how many faraday of charge are required?
C) 6.02 x 1023
D) none, charge is measured in Coulombs (C)
Faraday is a measure of 1 mole of electric charge equal to approximately 1 x 105 coulomb. In this question, 2 moles of electrons are required for the reduction, b) is correct.
A) 1, incorrect, 2 moles of charge are required.
B) 2, correct.
C) 6.02 x 1023, incorrect, Although this is the number of electrons in a mole of electrons, the faraday is a measure of 1 mole of charge.
D) none, charge is measured in Coulombs (C), incorrect, Although charge is measured in coulomb’s, it is also (less commonly) measured in faraday. Either unit may appear on the MCAT.