Test 4: Gases Lecture 1 Flashcards
5 Components of the Kinetic Molecular Theory of Gases
1 - Gases consist of many particles moving at random
2 - The amount of space occupied by the gas particles themselves is much smaller
than the amount of space between the particles
3 – Gas particles do not have appreciable attractive or repulsive forces between
them
4 – The average kinetic energy of gas particles is proportional to the temperature
5 – Collisions of gas particles are elastic
The amount of __occupied by the gas particles themselves is much __than the
amount of __between the particle
space; smaller; space
Gases consist of many particles moving __
at random
Gas can be contained into a small volume because it is __
highly compressible
Gas particles do not have appreciable attractive or repulsive forces between them because __
the particles are too far apart from one another
Average kinetic energy is proportional to the __
temperature
Collisions of gas particles are elastic, meaning that
no energy is gained or lost in the collision, only transferred.
Measurements of gas
pressure, volume and temperature
Symbol for pressure
Capital letter “P”
Pressure
The force exerted on an area
Unit of measurement for gases
Hg (Torr) and atm
atm
atmospheric pressure on earth
1 atm=__mm Hg
760 mm Hg
Volume (V)
measure of total space occupied.
Standard unit of Volume (V)
Liter/ mL
Do gases have a defined volume?
No, they expand to occupy any space they are in
Temperature (T) represents __ of the gas molecules
kinetic energy
For calculations involving the temperature of a gas we must always use temperature in units of
Kelvin, K
Celsius to Kelvin Formula
°C + 273.15 = K
Individual gas law’s describe the relationship between (4)
pressure, volume, temperature and molar
Individual Gas Law Name’s (4)
Boyle’s law, Gay-Lussac’s law, Charle’s law, Avogadro’s law
Boyle’s Law
The relationship between pressure and volume. No matter how the pressure or temperature changes from initial conditions, the product of the initial volume and pressure will always equal the product of the final volume and pressure
How is Boyle’s Law (pressure/volume) expressed mathematically?
P1V1 = P2V2
(at constant temperature)
Gay-Lussac’s Law
Relationship between pressure and temperature (at a constant volume)
How is Gay-Lussac’s Law (pressure & temperature) expressed mathematically?
P1/T1=P2/T2
The combined gas law allows us to
compare all three quantities (temp, pressure, volume) in a sample of gas where NONE of these remains constant.
Charles’s Law
for a sample of gas at constant pressure, Volume and Temperature are directly related, and the ratio of the two is constant.
How do we express Charles’s Law (volume & temperature) mathematically?
V1/T1=V2/T2
Cross multiply method
multiply the top factor on the left side with the bottom on the right side, and vice versa. These multiplied factors are equal.
V1/T1=V2/T2 -> V1T2=V2T1
Avogadro’s Law
at constant pressure and temperature, the volume of a gas is directly proportional to the number of moles it contains.
Avogadro’s law is expressed mathematically as
1mole gas=22.4 Liters (at STP)
STP
Standard temperature (0 °C) and pressure (1atm)
In Charles’s law temperature must be converted to
Kelvins
Individual gas laws are valid only at a __ temperature, volume and pressure
constant
The combined gas law allows us to compare
all three quantities in a sample of gas where NONE of these remains constant.
Mathematical expression of the combined gas law
P1V1/T1 =P2V2/T2
