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# Stoichiometry

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• at in order to convert from moles to grams we use the molecular weight of aluminum but why isn't that value multiplied by 2 since there are 2 Al atoms reacting. Instead of multiplying by 27 grams we should multiply by 54 grams. Let me know if i made a mistake or didn't understand it properly
• I understood him up until after he said that iron 3 oxide is 160 amus. I don't get the calculations he's doing after that. Can anyone help me?
(1 vote)
• There are 56amus in iron and 16amus in oxygen. To get the amount of amus in Fe2O3 which is iron III oxide, we simply multiply the amus of iron by 2 (56 x 2 = 112) and the amus of oxygen by 3 (16 x 3 = 48) and add them to get 160amus. This is because there are two iron atoms and three oxygen atoms in the iron III oxide molecule. Hope that helps!
(1 vote)
• What are industrial applications of stoichiometry?