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Homework Help: Hi i need some help

  1. Feb 24, 2010 #1
    1. The problem statement, all variables and given/known data
    How much dcm3NH3would we get if 2 mole of N2 react with the same amount of H2

    2. Relevant equations
    I tried this n=V/Vm then get V=n x Vm then get 2 mole x 22.41 dm3 x mole -1then get 44.82 dcm3 but i dont now if it is right so any help would be great

    3. The attempt at a solution
  2. jcsd
  3. Feb 24, 2010 #2
    If by dcm^3 you mean mass (d=m/v --->dv=m?) then you don't need to do all the stuff you wrote down. You need to write down the chemical reaction because the synthesis of ammonia will have a limiting reagent (I'll let you figure that out for yourself). From there you can figure out how many moles of ammonia are made and just use the molar mass to convert to g/Kg of whatever of ammonia.
  4. Feb 24, 2010 #3
    no i was meaning the volume
  5. Feb 24, 2010 #4
    Well regardless of what you are trying to find you need to start the problem the way I explained above. You will not get 2 mol of ammonia when you mix 2 mol of nitrogen and 2 mole of hydrogen because there will be a limiting reagent.

    The volume of the gas will depend on the pressure and temperature of the system and number of mols, the relationship is given by PV=nRT. T is temp in Kelvin, and R is the Rydberg constant (0.08206 L Atm/mol K), P is pressure measured in Atm, V is volume measured in L.
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