The diagram below shows an iron bar which supports a bridge. The iron bar is connected to a piece of magnesium metal.

The diagram below shows an iron bar which supports a bridge. The iron bar is connected to a piece of magnesium metal.

Explain why it is necessary to connect the piece of magnesium metal to the iron bar.

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Magnesium is above iron in the activity series. It supplies electrons to the iron bar hence prevents it from rusting.

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johnmulu answered the question on April 6, 2017 at 11:53

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