Which of the metals does not corrode inspite of favourable standard electrode potential?A. `Ti`B. `Al`C. both (1) and (2)D. `Fe`

Which of the metals does not corrode inspite of favourable standard el

1.	Which of the metals does not corrode inspite of favourable standard electrode potential?A. `Ti`B. `Al`C. both (1) and (2)D. `Fe`
Answer» Correct Answer - C Aluminium , a very active metal, reacts rapidly with `O_(2)` form the air to form a surface layer of aluminium oxide, `Al_(2)O_(3)`, that is so thin that it is trasparent. This very tough, hard substance is inert to `O_(2), H_(2)O`, and most other corrosive agents in the environment. In this way objects made of `Al` form their own protective layers and need not be treted further to inhibit corrosion. However, acid rain endangers structural `Al` by dissolving this `Al_(2)O_(3)` (amphoteric oxide) coating. Similarly `Ti` (which is often used to make sports bikes) does not corrode becuase of a hard, impenetrable layer of `TiO_(2)` that adheres to the surgace and protects themetal form further oxidation.

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Which of the metals does not corrode inspite of favourable standard electrode potential?A. `Ti`B. `Al`C. both (1) and (2)D. `Fe`

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