Calculating Equilibrium Concentrations, given K

Lo-tech!

There's nothing like a paper and pencil for working out a question.  Just because these questions are on a computer, don't forget the obvious.  You need to write out your solution on paper!

Remember that you enter numbers in scientific notation on your computer: 1.234E-05 for 1.234 x 10-5

Problems:

1. 0.100 mol of NO2 (g) is added to an evaculated 1 L container.  K for the reaction 2NO2 (g) N2O4 (g) is 170.  What is the equilibrium concentration of N2O4 and NO2?

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2. 4.00 x 10-2 mol of COCl2 (phosgene) is placed in a 1.0 L container and heated to 500K.  At this temperature K = 8.5 x 10-5 for the reaction

COCl2 (g) CO (g) + Cl2 (g)

What is the equilibrium concentration of CO (g)?

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3. 0.20 mol of NOCl was initially placed in a 2.0 L container at 280 șC.  K   = 2.70 x 10-3 for the reaction

2NOCl (g) 2NO (g) + Cl2 (g)

What is the equilibrium concentration of NO?

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4. Steam reforming of methane is used extensively in the petroleum industry to generate hydrogen gas.  Suppose that equal amounts of H2O and CH4 gases are fed into the reactor.  The reaction is in equilibrium

H2O (g) + CH4 (g) 3H2 (g) + CO (g)

at 1000 șC where K = 0.800.  In the products there are equal concentrations of water and methane of 0.280 mol/L.  What is the concentration of H2 and CO gases?

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