The Mole

90.0 grams H2O / 18.0 g/mole = 5.00 moles of H2O = 10.00 moles of hydrogen C : H = 4.00 : 10.00 ( 2 :5 ( C2H5 If the compound in #5 is know to be a gas at STP conditions, and a 2.50-gram sample is known to occupy 96.6 ml, what is the true, or molecular, formula of this compound? ................
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