{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

Gas Laws Lecture Kotz

# Gas Laws Lecture Kotz - Gas Laws Explores the relationships...

This preview shows pages 1–4. Sign up to view the full content.

1 Gas Laws MDI corporation prototype for vehicle that runs on compressed air. Explores the relationships between: Volume, V Temperature, T Amount (moles), n Pressure, P Pressure Pressure is defined as force per unit area: P = F/A In physics, the unit of pressure is the Pascal (Pa) and is equal to 1N/m 2 . Other units of pressure: Atmosphere: The average pressure of the atmosphere on the surface of the Earth at sea-level (atm) Torr: Unit of pressure based on the mercury barometer (torr). 1atm = 760torr = 101,300Pa Mercury Barometer The atmospheric pressure pushes the mercury column up 760mm, before the weight (Force) of the column down per unit area is equal to the upward pressure (Note the vacuum above the Hg column in the tube) 1mmHg = 1torr Pressure Units Summary: 1atm = 760mmHg (torr) = 101,300Pa = 101.3kPa (also 29.92”Hg, 1.013bar, 14.7psi) Measuring Sample Gas Pressure Open-end Manometer (Ma-naw-mah-ter) Closed-end Manometer Vacuum. The height of the Hg column only depends on the sample gas pressure

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
2 Three Relationships Boyle’s Law Boyle’s Law PV = constant (n, T kept constant) Inverse Relationship P 1 V 1 = P 2 V 2 Charles's Law V/T = constant (n, P kept constant) Direct Relationship V 1 /T 1 = V 2 /T 2 Avogadro's Law Avogadro's Law V/n = constant (T, P kept constant) Direct Relationship V 1 /n 1 = V 2 /n 2 Boyle’s Law Relationship Combined Gas Law: PV/nT = constant (T in Kelvins) 1 1 2 2 1 1 2 2 PV PV n T n T = Avogadro’s Hypothesis: Equal volumes of gases under the same conditions of temperature and pressure have equal numbers of particles (either molecules or atoms depending on the composition of the gas). V n at constant P and T Ideal gas Law: PV = nRT R = .0821L atm/mol K Standard Molar Volume Standard Molar Volume: At standard temperature and pressure ( STP = 1atm and 273.15K) 1 mole of any ideal gas has a volume of 22.4L Variations on the ideal gas law equation: PV = mRT/M (m = sample mass, M = molar mass of the gas) M = mRT/PV d = MP/RT (d = density of the gas in g/L) Stoichiometric Relationships
3 Gas Mixtures and Dalton’s Law of Partial Pressures Dalton’s Law of Partial Pressures: The total pressure exerted by a mixture of gases is equal to the sum of the partial pressures exerted by the separate gases.

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}