Final answer:
To calculate the corrosion penetration rate from passive current density, you would use a formula derived from Faraday's law of electrolysis. However, without additional information such as equivalent weight, atomic weight, and density of iron, the calculation cannot be completed.
Step-by-step explanation:
To calculate the corrosion penetration rate (CPR) using the passive current density for iron in a pH 11 solution, we can use Faraday's law of electrolysis, which can be written as:
CPR (mpy) = (0.129 × i × EW) / (d × A)
Where:
- i is the current density in µA/cm²,
- EW is the equivalent weight of iron,
- d is the density of iron in g/cm³,
- A is the atomic weight of iron.
To proceed, we need to convert the current density from microamps per square centimeter to amps per square meter (A/m²) and use known values for EW, d, and A. However, this information is not provided in the question, so we cannot complete the calculation.