OB: You will become a gas math master

1. OB: You will become a gas math master You will put this stuff on a leash and own it like a dog. What’s your dog’s name?

2. Avogadro’s Hypothesis This is so important, it’s one slide but it’s epic thinking. You should consider putting this statement (and diagram) in a frame, and hang it in your bathroom, forever. “Equal volumes of DIFFERENT gases, at THE SAME temperature + pressure have the SAME number of moles, and the SAME number of particles”.

3. “Equal volumes of DIFFERENT gases, at THE SAME temperature + pressure Have the SAME number of moles, and the SAME number of particles”. NH3 He CO2

4. You can change the volumes to any number (and do the mole island math) to see all gases will have the same number of particles, same number of moles, and same pressure and volume. It’s all connected.

5. Draw these three graphs, casually, but correctly. Use P, V, and T for axis labels. Draw proper lines. ALSO, indicate if each graph is directly or inversely proportional. Volume as a function of Temperature. Pressure as a function of Volume. Pressure as a function of Temperature.

6. Draw these three graphs, casually, but correctly. Use P, V, and T for axis labels. Draw proper lines. ALSO, indicate if each graph is directly or inversely proportional. Volume as a function of Temperature. Pressure as a function of Volume. Pressure as a function of Temperature. V P P • T • V • T DIRECTLY Proportional INVERSELY Proportional DIRECTLY Proportional This one is hard to draw, but it’s a smooth curve-alicious curve

7. Convert 145.6 kPa into atmospheres Convert 1.06 atm into millimeters of mercury Change 844 mm of Hg into kilopascals

8. Convert 145.6 kPa into atmospheres Convert 1.06 atm into millimeters of mercury Change 844 mm of Hg into kilopascals • 1.0 atm101.3 kPa 145.6 kPa1 X • = 1.437 atm (4SF) • 760 mm Hg1.0 atm 1.06 atm1 X • = 806 mm Hg (3SF) • 101.3 kPa760 mm Hg 844 mm Hg1 X • = 112 kPa (3SF)

9. Ideal Gases vs. Real Gases Ideal gases do not exist, except as the idea of “perfect” gases. Real gases are real, they are the ones you know, like N2, CO2, O2, NH3, Ne, etc. Most real gases remain gases because of the kinetic molecular theory of gases (and the Sun’s free energy each day). Ideal gases can’t become liquids, no matter the temperature or pressure, since they’re FAKE. Real gases can become liquid or solid. Real gases act most ideally under these 2 conditions: High temperature and low pressure. Because with high temperature, they bang around so hard, they are less likely to stick together. With low pressure, they are not as likely to even bump into each other, which makes it hard to form into a liquid.

10. Ideal Gases vs. Real Gases When comparing different real gases, at the same temperature and pressure, the gas with the smallest particles, are the most ideal. If you had 2.45 liters of neon, of carbon dioxide, and of propane, all at STP, which would act MOST IDEAL? Neon = single atoms = MOST IDEAL Carbon dioxide = 3 atom molecules Propane (C3H8) = 11 atom molecules

11. NOW:54 gas problems, numbers: 22 – 33 All answers are ONLINE, arbuiso.com handout section, 54 gas questions ANSWERS There will be a take home celebration on gases TUESDAY night. YOU MUST RETURN IT ON WEDNESDAY or lose 25 points. Problems? See me ASAP!