Gas Laws Flashcards
Gas
a substance that has no well defines boundary but diffuses rapidly to fill the container in which it is placed
boyles law
at constant temperature the volume of a fixed mass of gas is inversely proportionate to its pressure
charles’ law
at constant pressure the volume of a fixed mass of gas is directly proportional to its temperature as measured on the Kelvin scale
Gay lussacs law of combining volumes
in a reaction between gases the volumes of the reacting gases and the volume of any gaseous products are in the ratio of small whole numbers provided the volumes are measured at the same temperature and pressure
avogadros law
equal volume of gases contain equal number of molecules under the same conditions of temperature and pressure
ideal gas
a gas that perfectly obeys all of the assumptions of the kinetic gas theory under all conditions of temperature and pressure
real gas
different from an ideal gas because forces of attraction and repulsion do exist between molecules and the volume of the molecules is not always negligible
How do you convert from °C to Kelvin?
Add 273 to the amount of °C
How to convert from cm^3 to m^3
Add x10^-6 to the end
How to convert from cm^3 to Litres
Cm^3 divide by 1000
How to convert from litres to m^3
Litres divided by 1000
How to convert from kPa to Pa
Multiply by 1000
What are the conditions of S.T.P
Temp- 273 K
Pressure- 100kPa
Molar volume- 22.4L
What are the conditions of R.T.P
Temp- 298K
Pressure- 100kPa
Molar volume-24L
What does STP stand for
Standard temperature and pressure
What does RTP stand for
Room temperature and pressure
Explain boyles law
- Expanding the container increases volume and decreases the pressure
- Making the container smaller decreases the volume and increases the pressure
What gases follow boyles law
For all gases
What unit does temperature have to be in for Charles’ law to be true?
When temperature is in KELVIN
What is the combined gas law formula?
(P1)(V1)/(T1)=(P2)(V2)/(T2)
What are the important things to remember when using the combined gas law formula
Gas 1+2 have to all have the same unit
Temperature HAS to be in KELVIN
How do you find the volume of a gas?
Moles x molar volume
(Molar volume is either stp or rtp)
Volume must be in L
Give 2 assumptions of the kinetic gas theory
- No attractive or repulsive forces between molecules/point particles of the gas
- Gas molecules are so small and so far apart that the actual volume of the point particles is negligible compared to the space that they occupy
- The average Kinetic energy of the molecules in a gas is directly proportional to the temperature
Limitations of the kinetic gas theory
- All real gases do experience tiny attractive/repulsive forces between molecules. Some molecules have permanent dipoles and form dipole dipole or hydrogen bonding forces. Or if it is non polar it will form van dear waals
- It is not true that the volume is negligible compared to the space particles occupy. Under high pressure when molecules are forced close together, their volumes are not negligible compared to the space they occupy
