Gases and Gas Laws Flashcards
What is STP?
760 mmHg (760 torr, 1 atm, 101.325 kPa) & 273 K (0*C)
How is a manometer used?
Gas in a bulb on one side of a U and open to the air on the other with Hg in the U. Unless otherwise told, assume STP. If the pressure in the bulb is higher, the Hg will rise on the other side. If lower it will fall on that side. P = atmospheric +/- mm diff in Hg. (the +/- is for the less than or greater than)
What is Kinetic Molecular Theory?
Matter in all forms is composed of super-small particles. All particles are in constant motion, the extent of which is determined by their temperature (kinetic energy) and state. When the particles collide w/ each other or the walls of a container, there is no loss in energy.
What are temperature readings?
An average of the kinetic energies of a sample –> each particle is a bit different, so it is an average.
What is diffusion?
Spreading out
What is effusion?
Passing through a small opening
What are the gas laws?
Graham’s Law, Charles’s Law, Boyle’s Law, Gay-Lussac’s Law, Dalton’s Law, Avogadro’s Law, and ideal gas law.
Graham’s Law
Rate of effusion of a gas is inversely proportional to the square root of its molecular mass.
Rate A √molec. Mass B
——— = ———————–
Rate B √molec. Mass A
Charle’s Law
V/T
Boyle’s Law
PV
Gay-Lussac’s Law
P/T
Dalton’s Law of Partial Pressures
Ptot = P1+P2+P3+…
If a gas is collected over water, what correction is necessary to the measurement of pressure?
Pgas = Patm - Ph20 (Ph2o is 23.8 mmHg at 298K)
Eudiometer Corrections
Convert to mmHg (divide water by 13.6). If level inside is higher, subtract diff from outside pressures. If level inside is lower add the diff to the outside pressure.
What is the Ideal Gas Law?
PV = nRT, R = 0.0821 L atm/mol K
