Answer all questions using potansiostatic plots given to you.

a) What are corrosion potentials of Zn and Fe in 3 wt.% aerated NaCl solution? Write anodic and cathodic reaction before and after cathodic and anodic polarization. Explain the potansiostatic plots of Fe and Zn.

b)Where is the anode when they (Zn-Fe) are connected by conductive wire? And write anodic and cathodic reaction or s for galvanic couples.

c) Determine the galvanic currents and corrosion rate (mm/year) in the anode in a couple between equal areas of iron and Zn from data given to you.

Density of Zn=7.13 gr/cm³ and density of Fe=7.87 gr/cm³. Equivalent weight of Fe= 27.92 gr/eq. Equivalent weight of Zn= 32.69 gr/eq.

d) Show the effect of 10:1 ratio of cathode to anode ratio in Fe-Zn couple using polarization diagrams in E vs. log curre

e) Can Fe protected by Zn (lowering corrosion rate of Fe or being immune)? Why? What is it called?nt. Calculate the corrosion rate.