when 18.66 g of magnesium react with 22.28g of oxygen, 30.94g of megnesium oxdie forms. If all the magnesium reacts, how many grams of oxygen remain un-reacted?
2Mg + O2 ==> 2MgO
Convert 18.66 g Mg to mols.
Convert mols Mg to mols oxygen (which is mols oxygen USED).
Convert mols oxygen to grams and subtract initial mols - mols used = mols remaining.
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