The chemical formula of rust, which is formed on the surface of iron in the presence of oxygen and m

JAMB Chemistry 2023 66 views

The chemical formula of rust, which is formed on the surface of iron in the presence of oxygen and moisture is

  1. FeO
  2. Fe₂O₃ ✓
  3. Fe₃O₄
  4. Fe(OH)₃

Explanation

Rust is iron(III) oxide, Fe₂O₃. When iron contacts oxygen and water, it slowly forms this reddish-brown compound.

FeO is iron(II) oxide. Fe₃O₄ is magnetite. Fe(OH)₃ is iron hydroxide. None of these form the common rust you see.

Remember: Rust makes iron weak and flaky. Painting iron prevents oxygen contact and stops rust.

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