Wednesday, 15 May 2013

2.34 describe the conditions under which iron rusts

Water and oxygen are needed to rust iron: iron that reacts with these becomes hydrated iron(iii) oxide.

9 comments:

  1. Water isn't needed. Only oxygen is. It's just that there is oxygen in water so iron will rust

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    1. water IS need... there's a good visual representation of the conditions here: http://www.bbc.co.uk/schools/gcsebitesize/science/ocr_gateway/chemical_resources/making_carsrev1.shtml

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    2. You do need water for the rusting of iron, just not the oxidation. This is the only metal where this is true. Rusted iron is orange and weak, whereas oxidised iron is black and strong. Often, things made of iron are oxidised to protect them from rusting.

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  2. Electrolytes such as salt also help speed up the process

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  3. This comment has been removed by the author.

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  4. Your blog has been so useful! It's helped me a lot :)

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  5. Can I also write ferric oxide for the product? I read that somewhere...
    Thank you so much for the blog though!

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    1. In these circumstances, you can't, as it's RUSTED iron, which also has H2O attached to it (Fe2O3.nH2O), whereas ferric oxide is Fe2O3

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