The correct answer is Equivalent weight. Explanation & Key Takeaways: • Faraday's laws of electrolysis are concerned with Equivalent weight. • The laws state that the amount of chemical change produced by the current at an electrode-electrolyte boundary is proportional to the quantity of electricity used and the amount of chemical change produced by the same quantity of electricity. • Different substances are proportional to their equivalent weights. • The equivalent weight of an element or radical is equal to its atomic weight or formula weight divided by the valence it assumes in compounds. The unit of equivalent weight is the atomic mass unit. Related Concepts: • The total weight of an atom is called the atomic weight. It is approximately equal to the number of protons and neutrons with a little extra added by the electrons. • Molecular weight is also called molecular mass. The molecular mass is the mass of a given molecule. it is measured in daltons. • The atomic number is the number of protons in the nucleus of an atom.