Steel oxidation experiment. From left to right the test tubes contain steel nails. Oxidation of the iron in the steel requires both water and oxygen t

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Steel oxidation experiment. From left to right the test tubes contain steel nails. Oxidation of the iron in the steel requires both water and oxygen to be present. The first nail is in ordinary water which contains dissolved oxygen, and the nail has rusted to form iron oxide (orange). The second nail is sealed in air with silica gel that absorbs moisture in the air. The seal prevents more water vapour entering the test tube, and so rusting does not occur. The third nail is in boiled water (boiling the water removes the dissolved oxygen). A liquid paraffin layer prevents oxygen dissolving back into the water, so rusting also fails to occur here.

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Size: 5173px × 3449px
Photo credit: © MARTYN F. CHILLMAID/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: apparatus, chemical, chemistry, comparing, equipment, experiment, gas, gel, glassware, iron, laboratory, liquid, metal, nail, oxide, reacting, reaction, rust, school, science, silica, studio, test, tube, water