Current Density / Acm 1. A plain steel plate 1 cm in area is in full...

 

Transcribed Image Text:

Current Density / Acm 1. A plain steel plate 1 cm in area is in full contact with an acid solution with concentration of H+ ions =1M (mol/liter) and PH2=1 atm. The activity of Fe2+ ions is 10-6. There are no other important ions or gases in the solution. The exchange current density of all the relevant reactions is 10-7 A/cm, and the absolute values of the Tafel slopes are all 100 mV/decade. Assume simple activation polarization. a) Find the corrosion rate (in A/cm) of the steel. b) Find the corrosion potential (in V, SHE scale) Hint: As a first step, use the simplified version of the Nernst equation E E (0.06 V/n) log10(1/a+n) to find the equilibrium potential for the Fe/Fe+ - system. 10-2 10-3 10-4 10-5 10-6 10-7 1 Current Density / Acm 1. A plain steel plate 1 cm in area is in full contact with an acid solution with concentration of H+ ions =1M (mol/liter) and PH2=1 atm. The activity of Fe2+ ions is 10-6. There are no other important ions or gases in the solution. The exchange current density of all the relevant reactions is 10-7 A/cm, and the absolute values of the Tafel slopes are all 100 mV/decade. Assume simple activation polarization. a) Find the corrosion rate (in A/cm) of the steel. b) Find the corrosion potential (in V, SHE scale) Hint: As a first step, use the simplified version of the Nernst equation E E (0.06 V/n) log10(1/a+n) to find the equilibrium potential for the Fe/Fe+ - system. 10-2 10-3 10-4 10-5 10-6 10-7 1