The coverage of corrosion in the steel reinforcing rods rebar of concrete is calculated by the galvanic cell shown in the diagram of the instrument. The half-cell of the probe is habitually a AgCl/Ag redox couple:
AgCl + e-= Ag Cl- (1.0 M) E standard= 0.23 V
Corrosion is said to be severe if the cell potential is calculated at greater than 0.41 V. Under these conditions, Explain what is the iron(II) concentration on the rebar?
Fe 2+ + 2e-= Fe E standard= -0.44 V