Cu²⁺+2e⁻→Cu, M=127/2 g/mol, Q=2F ⇒ n=1 mol, mass = 127/2 g

Sympy-exact symbolic witness of Faraday's law applied to copper electrodeposition from Cu²⁺ solution. Setup: M_Cu = 63.5 g/mol = 127/2 (exact rational), z_Cu = 2 (two-electron reduction), pass Q = 2 F coulombs (two Faradays — pedagogical…