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Question
Give a reason why iron objects rust easily but the iron pillar at Qutab Minar has not rusted over the years.
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Solution
The iron pillar at Qutab Minar has not rusted for 1600 years because of the following reasons:
- The high purity and great mass of iron may have created a temperature stabilizer thus reducing the condensation of moisture on it.
- The protective scale or passive iron coating formation on the surface, better forge welding and absence of impurities in iron – also may have dissuaded corrosion.
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