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The time required to uniformly corrode (zinc coating) the steel to a thickness of
Answer to Problem 56AAP
The time required to uniformly corrode the steel to a thickness of
Explanation of Solution
Write the expression for corrosion rate.
Here, the corrosion rate is
The current density is expressed as,
Substitute
Here, the corrosion rate per area is
Write the formula for time required for corrosion of required depth.
Conclusion:
Refer Table 13.1, “Standard electrode potentials at 25 °C”.
The anodic reaction of zinc is as follows:
Here, the number of electrons produced is,
Refer Figure 2.3, “Periodic Table of Elements”
The atomic mass of zinc is,
Substitute
The density of the zinc is
Substitute
Thus, the time required to uniformly corrode (zinc coating) the steel to a thickness of
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