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A mixture of oxygen, nitrogen, and hydrogen gases exerts a total pressure of 74 kPa at 0 degrees Celsius.  The partial pressure of the oxygen is 20 kPa and the partial pressure of the nitrogen gas is 41 kPa.  What is the partial pressure of the hydrogen gas in this mixture?

A compound consists of 25.9% nitrogen and 74.1% oxygen by mass.  Calculate the empirical formula below.   All relevant work must be shown.  Please type in your calculations (no attachments)

2 Al(s)  +  2 H3PO4(aq)  –>  2 AlPO4(aq)  +  3 H2(g) What type of reaction is shown above?

Given the reaction: C3H8(g)  +  5 O2(g)  –>  3 CO2(g)  +  4 H2O(g) What is the total volume of water vapor formed when 8.00 L of C3H8 is completely oxidized?

Chromium metal has a specific heat capacity of 0.461J/g ° C. Calculate by how much the temperature of the sample will rise if 100. J of heat is applied to 5.00g sample of chromium at 20 ° C.  Answer: [BLANK-1] ° C (Provide your answer with correct sig. figs. and DO NOT include unit in your answer, as it has been provided)

Using the following diagram:   If CO2 is at a pressure of 150 kPa and 100 Kelvin, and the temperature is increased to 300 K, what phase change has occurred?

Given the reaction: 4 NH3  +  5 O2  –>  4 NO  +  6 H2O If 8.0 moles of NH3 reacts with 8.0 moles of O2, what is the limiting reactant?

Lithium has two stable isotopes.  An average sample of lithium would contain the following:   4.85% of lithium-6 and 95.15% of lithium-7.  Which mathematical set-up would determine the atomic mass of naturally occurring lithium?

Please indicate whether the following are empirical and molecular formulas.   Please indicate empirical or molecular, you do not write the word “formula”. MgCl2 [1] N2O4 [2] Al2O3 [6]

Given the reaction: 2 Na  +  2 H2O  –>  2 NaOH  +  H2 What is the total number of moles of hydrogen gas produced when 4.0 moles of sodium reacts completely?