It is similar to ordinary soap, but the atoms of iron help form tiny particles that are easily removed magnetically.

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Mr Bush is like a magnet beneath a piece of paper: as he moves, the iron filings silently form into new patterns.

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As the bacteria produced oxygen, the two compounds reacted to form iron oxide, which precipitated onto the seafloor in great layers of rust.

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Upon exposure to water and oxygen, these minerals oxidize to form acid-, iron- and sulfate-rich drainage.

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Highly organized professional educators, sympathetic liberal legislators and a constituency of manipulable education consumers form a classic "iron triangle" that has proved impervious to reform.

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The machine blends iron, bleach and sodium hydroxide to form a dark purple liquid mixture of ferrate, salt and water that gets metered into the water supply. (The color disappears instantly as it reacts with the water.) Common disinfectants ozone and chlorine can turn the water cloudy or, worse, leave behind harmful chemical by-products.

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Their results suggest 55 Cancri e is largely composed of carbon (in the form of graphite and diamond), iron, silicon carbide, and, potentially, silicates.

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