Gas Laws & Kinetic Molecular Theory
Core idea: matter is made of particles that are always moving.
Key Principles:
More kinetic energy - higher temperature
Slower particle movement - less heat present
Energy and States of Matter:
Most to Least energy: Gas, Liquid, Solid
Changes in energy = changes in states of matter
Brownian Motion: random particle movement suspended in a fluid
cause: continuous collisions w/ smaller, faster moving particles
significance: evidence that particles are always in movement
Temperature: measurement of the average kinetic energy of particles in a substance
the higher the kinetic energy, the higher the temperature
measured in kelvin +273
States of Matter and Phase Changes
energy and states
solid - (particles) vibrates in place - least (energy) level
liquid - slide past each other - moderate level
gas - move freely and rapidly - highest level
Phase Diagram
purpose: to show how pressure and temperature determine the state of a substance
used to identify:
freezing/melting point
vaporization/condensation point
sublimation point
triple point: specific temperature + pressure where all states of matter coexist.
pressure: force presented by gas particles colliding w/ the walls of a container
formula: p = force/area (dependent on)
units: pascal (pa), atmosphere (atm), millimeters of mercury (mmHg) or Torr
volume: space that matter occupies
units: L, mL
more gas particles = more volume
volume = depends on pressure and temperature
Three Laws of Gases
Boyle
inverse relationship between pressure and volume when temp. and gas amount are constant
P1V1=P2V2
if pressure increases, volume decreases and viceversa
Charles
direct relationship between temperature and volume when pressure and gas amount are constant
V1/T1=V2/T2
if temp. increases, volume increases
Gay
direct relationship between pressure and temp. when volume is constant
P1/T1=P2/T2
if temp. increases, pressure increases
Combined Gas Law
pressure, volume, temp all change while gas amt. is constant
P1V1/T1=P2V2/T2