Mechanics of Breathing mberlake, Chemistry 7 th Edition, page 254
Dec 28, 2015
Mechanics of Breathing
Timberlake, Chemistry 7th Edition, page 254
Air Pressure
Water pressure increasesdue to greater fluid aboveopening.
“One Minute Left”
SCUBA Diving
• Self Contained Underwater Breathing Apparatus• Rapid rise causes “the bends”
– Nitrogen bubbles out of blood
rapidly from pressure decrease
Must rise slowly to the surface to avoid the “bends”.
Exchange of Blood Gases
Timberlake, Chemistry 7th Edition, page 273
Solubility of Carbon Dioxide in Water
Temperature Pressure Solubility of CO2
Temperature Effect
0oC 1.00 atm 0.348 g / 100 mL H2O20oC 1.00 atm 0.176 g / 100 mL H2O40oC 1.00 atm 0.097 g / 100 mL H2O60oC 1.00 atm 0.058 g / 100 mL H2O
Pressure Effect
0oC 1.00 atm 0.348 g / 100 mL H2O0oC 2.00 atm 0.696 g / 100 mL H2O0oC 3.00 atm 1.044 g / 100 mL H2O
Notice that higher temperatures decrease the solubility and that higher pressures increase the solubility.
Corwin, Introductory Chemistry 4th Edition, 2005, page 370
Vapor Pressure of Water Temp. Vapor Temp. Vapor Temp. Vapor (oC) Pressure (oC) Pressure (oC) Pressure (mm Hg) (mm Hg) (mm Hg)
0 4.6 21 18.7 35 41.2
5 6.5 22 19.8 40 55.3
10 9.2 23 21.1 50 71.9
12 10.5 24 22.4 55 92.5
14 12.0 25 23.8 35 118.0
16 13.6 26 25.2 40 149.4
17 14.5 27 26.7 40 233.7
18 15.5 28 28.4 55 355.1
19 16.5 29 30.0 35 525.8
20 17.5 30 31.8 40 760.0
Corwin, Introductory Chemistry 4th Edition, 2005, page 584
Solventmolecules
Nonvolatilesolutemolecules
Solventmolecules
Nonvolatilesolutemolecules
Henry’s LawHenry’s law states that the solubility of oxygen gas is proportional
to the partial pressure of the gas above the liquid.
EXAMPLE:
Calculate the solubility of oxygen gas in water at 25oC and a partial pressureof 1150 torr. The solubility of oxygen in water is 0.00414 g / 100 mL at 25oC and 760 torr.
0.00414 g / 100 mL1150 torr
760 torr= 0.00626 g / 100 mL
solubility x pressure factor = new greater solubility
Corwin, Introductory Chemistry 4th Edition, 2005, page 370
Note: 1 torr = 1 mm Hg