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What is the percent yield when 1.72 g of H2O2 decomposes and produces 375 mL of O2 gas measured at 42 oC and 1.52 atm?  The molar mass of H2O2 is 34.02 g∙mol–1.                2H2O2(aq)2H2O(l) + O2(g)   Data sheet and Periodic Table

Which set of quantum numbers is correct and consistent with n = 4?  Data sheet and Periodic Table

What is the empirical formula of a compound that contains 72.0% carbon, 12.0% hydrogen and 16.0% oxygen by mass?  Data sheet and Periodic Table

Strontium (Sr, atomic number 38, average atomic mass = 87.62) naturally exists as 4 stable isotopes with masses of 84, 86, 87, and 88.  Which statement is correct?  Data sheet and Periodic Table

What is the formal charge on nitrogen in the nitrate ion?           Data sheet and Periodic Table

What is the orbital diagram for the valence electrons in a ground state atom of nitrogen?   Data sheet and Periodic Table

An enriched sample of carbon contains 20.0% 12C and 80.0% 13C.  Which figure shows this sample?Stem image:       Key:         Data sheet and Periodic Table

The figure represents the initial contents of a reaction vessel mixture of nitrogen monoxide (NO) and oxygen (O2) at a pressure of 1 atm.  Keeping the volume and temperature constant, what are the final total pressure (Ptot) and partial pressure of nitrogen dioxide (PNO2) when the reaction is complete (assuming a 100% yield)?             2NO(g) + O2(g)2NO2(g)             Data sheet and Periodic Table

What is the classification of the substance in the figure?         Data sheet and Periodic Table

In any neutral atom, there are equal numbers of  Data sheet and Periodic Table