General Chemistry Chapter 8: The Gas Phase Flashcards
(23 cards)
Are gases fluids?
yes; they conform to the shape of their containers
Gases are compressible or nah?
yes – hella
What are the variables of gas systems?
temperature, pressure, volume, and number of moles
1 atm = ? mmHg = ? torr = ? kPa
1 atm = 760 mmHg = 760 torr = 101.325 kPa
What does a simple mercury barometer measure?
incident pressure
standard temp and pressure
273 K and 1 atm
What do equations for ideal gases assume?
negligible mass and volume of gas molecules
ideal gas law
describes the relationship between the four variables of the gas state for an ideal gas
Avogadro’s principle
a special case of the ideal gas law for which the pressure and temperature are held constant; it shows a direct relationship between the number of moles of gas and volume.
Boyle’s law
temperature and number of moles are held constant
Charles’s law
pressure and number of moles are held constant
Gay-lussac’s law
volume and number of moles are kept constant
Dalton’s law of partial pressure
states that individual gas components of a mixture of gases will exert individual pressures in proportion to their mole fractions
Henry’s law
the amount of gas dissolved in solution is directly proportional to the partial pressure of that gas at the surface of a solution.
Kinetic molecular theory
attempts to explain the behavior or gas particles.
Assumptions of the kinetic molecular theory
- negligible volume
- no intermolecular attractions or repulsions
- undergo random collisions with each other and the walls of the container
- collisions between gas particles and with the wall of the container are elastic.
- average kinetic energy of gas particles is directly proportional to temperature
Graham’s law
describes the behavior of gas diffusion or effusion, stating that gases with lower molar masses will diffuse or effuse faster than gases with higher molar masses at the same temperature.
Diffusion
spreading out of particles from high to low concentration.
Effusion
movement of fas from one compartment to another through a small opening under pressure
Real gases
deviate from ideal behavior
moderately high pressures, low volumes or low temperatures… real gases:
occupy less volume than predicted because they have intermolecular attractions
extremely high pressures, low volumes or low pressure… real gases:
more volume than predicted because they occupy physical space.
Van der Waals equation of state
used to correct the ideal gas law for intermolecular attractions (a) and molecular volume (b)
