Question

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

C (mol/L)	P (atm)	k (mol/L⋅atm)	T (∘C)
3.80×10−2	1.00		20.0
4.90×10−2			20.0
	1.00	3.40×10−2	25.0

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

What pressure is required to achieve a CO2 concentration of 4.90×10−2 M at 20∘C?

At 1 atm, how many moles of CO2 are released by raising the temperature of 1 liter of water from 20∘C to 25∘C?

Answer 1

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

    Henry's law constant   = concentration / pressure

    Henry's law constant = 3.80×10⁻² mole / L atm

2) What pressure is required to achieve a CO2 concentration of 4.90×10−2 M at 20∘C?

henry's law constant = concentration / pressure

3.80 x 10^-2 = 4.90 x 10^-2 / pressure

pressure = 1.29 atm

3) At 1 atm, how many moles of CO2 are released by raising the temperature of 1 liter of water from 20∘C to 25∘C?

concentration = henry's law constant x pressure

                       = 3.40×10⁻² x 1.00

                      = 3.40 x 10^-2 M

change in concentration = 4.90 x 10^-2 - 3.40 x 10^-2

                                        = 0.015 M

concentration = moles / volume

0.015 = moles / 1 L

moles = 0.015