Where does this come from, and can I check it?

Zinc or aluminium anodes bolted to a steel hull dissolve first, protecting the steel from seawater. The figure is taken from Britannica, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.

Is this really a technology fact?

Yes. It sits on the Technology shelf, one of 2,600 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.

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The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.

Mondo Knows Facts

Ships carry blocks of metal meant to corrode

Zinc or aluminium anodes bolted to a steel hull dissolve first, protecting the steel from seawater Steel in seawater forms small electrochemical cells where different areas act as anode and cathode, and the anodes rust away quickly. Bolting on a metal with a lower electrode potential, such as zinc or a suitable aluminium alloy, makes the hull the cathode instead. Anodes are replaced at each dry docking, and impressed current systems do the same job with a power supply. It sits in Mondo's technology collection, one of 200 facts that each trace back to the reference below.

Where this comes from

Britannica

Facts that can change over time are reviewed and updated. If something here looks wrong, Mondo would rather know than be confidently incorrect.

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Tags: ships, corrosion, materials

Ships carry blocks of metal meant to corrode: the short answers

Where does this come from, and can I check it?: Zinc or aluminium anodes bolted to a steel hull dissolve first, protecting the steel from seawater. The figure is taken from Britannica, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.
Is this really a technology fact?: Yes. It sits on the Technology shelf, one of 2,600 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.
What else can I read about it?: The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.