Question- A gas contains a mixture of NH3(g) and N2H4(g), both of which react with O2(g) to form NO2(g) and H2O(g). The gaseous mixture (with an initial mass of 61.00 g) is reacted with 10.00 mol O2, and after the reaction is complete, 3.970 mol of O2 remains. Calculate the mass percent of N2H4(g) in the original gaseous mixture.

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