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### Topic: Problem of the week - 21/05/2012  (Read 7785 times)

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#### Borek

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##### Problem of the week - 21/05/2012
« on: May 21, 2012, 06:19:57 AM »
Another (simple) one taken from the old publication:

Gaseous mixture contained 51.3% (v/v) of H2S, the rest was CO2. 1750 mL of the mixture (measured at 760 mm Hg and 21 °C) was heated to 350 °C, cooled, and pumped through a CaCl2, increasing its mass by 34.7 mg. What is the equilibrium constant of the carbonyl sulfide synthesis from H2S and CO2 at 350 °C?
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#### sjb

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##### Re: Problem of the week - 21/05/2012
« Reply #1 on: May 26, 2012, 10:14:07 AM »
Another (simple) one taken from the old publication:

Gaseous mixture contained 51.3% (v/v) of H2S, the rest was CO2. 1750 mL of the mixture (measured at 760 mm Hg and 21 °C) was heated to 350 °C, cooled, and pumped through a CaCl2, increasing its mass by 34.7 mg. What is the equilibrium constant of the carbonyl sulfide synthesis from H2S and CO2 at 350 °C?

OK, here's a start

CO2 + H2 COS + H2O

CaCl2  CaCl2.6H2O (not sure of the exact formula of the hydrate, could be di, or tetra? May be irrelevant)

34.7 mg increase in the weight of CaCl2, means (34.7 x 10-3/18.02) mol of water.

#### Rutherford

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##### Re: Problem of the week - 21/05/2012
« Reply #2 on: May 26, 2012, 11:24:10 AM »
I got 3.062*10-3.

#### Borek

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##### Re: Problem of the week - 21/05/2012
« Reply #3 on: May 26, 2012, 04:10:53 PM »
Close, but not perfect.
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#### Sophia7X

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##### Re: Problem of the week - 21/05/2012
« Reply #4 on: May 26, 2012, 05:19:39 PM »
0.00282?
Entropy happens.

#### Borek

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##### Re: Problem of the week - 21/05/2012
« Reply #5 on: May 26, 2012, 05:26:03 PM »
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#### Rutherford

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##### Re: Problem of the week - 21/05/2012
« Reply #6 on: May 27, 2012, 04:09:24 AM »
Done more precisely and got that k=3.1507*10-3.

#### Borek

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##### Re: Problem of the week - 21/05/2012
« Reply #7 on: May 27, 2012, 04:26:20 AM »
3.15×10-3 it is

Compare E. Terres, H. Wesemann, Angew.Chem. 45, 795 (1932).
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