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smaturana123
how many moles of O2 are needed to completely react with 2.5 moles of Fe
Start by writing a balanced equation between oxygen and iron. Once you have that equation multiply 2.5 moles by the value for O2
I agree with abb0t. Always start with the balanced equation. 2Fe+O2--> 2FeO. Now notice that the ratio of moles is 2moles of Fe require 1 mole of O2. 2Fe=1O2