1 analysis shows a compound to contain 36.3% oxygen and 54.545% carbon by mass. The reminder is Hydrogen. If the compound is known to have a molecular mass in the range 70----100, determine the molecular formula of the compuind

the mole

what mass of potassium suphite ( Mr=158) is needed to react with an excess of dilute nitric acid to produce 780cm3 (the 3 is the little 3 at the top) of SO2 gas (at stp)?
K2SO3 + 2HNO3 2KNO3 + SO2 + H2O

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