The following table provides some information on carbon dioxide solubility in wa

Question

The following table provides some information on carbon dioxide solubility in water.

What is the Henry's law constant for CO2 at 20C?

Express your answer in mol L1 bar1 to four decimal places.

What pressure is required to achieve a CO2 concentration of 0.0980 mol L1 at 20C?

Express your answer to three significant figures and include the appropriate units.

Part C

At 1.01 bar, how many moles of CO2 are released by raising the temperature of 1 litre of water from 20C to 25C?

Express your answer to four decimal places and include the appropriate units.

Sgas
(mol L1) Pgas
(bar) kH
(mol L1 bar1) T
(C) 0.0380 1.01 20.0 0.0980 20.0 1.01 0.0340 25.0

Explanation / Answer

At a constant temperature, the amount of a given gas dissolved in a given type and volume of liquid is directly proportional to the partial pressure of that gas in equilibrium with that liquid.

k(T) = k(T) e^(-C((1/T)-(1/T)))
k(T) is Henry's constant at T. T is in kelvin.
T = 298 K
k(293) = k(298)e^(-2400((1/293)-(1/298))) = 0.87k(298)

I'm trying to make sense out of the information given here. Above is some information that I got from Wikipedia. The third line of your table agrees with a table in Wikipedia. C = 3.40×102 on the third line. (That chart is not shown above.)
I'm not sure if "k" in your chart is the standard k at the standard temperature, 298 K, or the k at the given temperature, 20 C = 293 K.
My calculation using the formula and data from wikipedia does not agree with the values of C in your chart, so I'll use your values.

I get that the answer to the question "What is the Henry's law constant for co2 at 20 C?" is read from the first line of the table.

The answer to "What pressure is required to achieve a concentration of 0.098 at 20 C?" is found by (1 atm)(0.098)/(3.70×102) = 2.6 atm. That's P in the second line. I guess k in lines 1 and 2 to be 3.70×102.

As for the initial question "At 1 atm, how many moles of CO2 are released by raising the temperature of 1 liter of water from 20 to 25 C?":
At 20K 0.037 moles CO2 dissolve in 1 liter of water.
At 25K 0.034 moles CO2 dissolve in 1 liter of water.
Subtract the two 0.037 - 0.034 = 0.003 to find that 0.003 moles of CO2 are released from solution when the temperature of 1 liter of water is raised from 20C to 25C.

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