Topic 5-Kinetic Theory And Gases Flashcards
What is the kinetic theory of liquids
Weaker forces of attraction Close together Can't move past each other Irregular arrangement More energy than solids, move in random directions at slow speeds
Kinetic theory of gases
Most have no forces of attraction
More energy than liquids or solids
Free to move in random directions at high speeds
Why should Erin and Yas keep revising and going strong for they’re last day of revision
1) for they’re futures Dr Irwin and Dr Rivett
2) so they have no regrets over exams
3) so they can get on the A+ Paxton scheme (realistic Erin!!!)
4) so they can be the real life versions of Megan Hunt (aka Sass)
The small particles of gas take up hardly any space, so most gas is…
Empty space
What temperature is 0 kelvin in Celsius
-273
What is the freezing point of water on the Kelvin scale
273K
What is the boiling point of water on the Kelvin scale
373K
What do you do to convert Celsius into kelvin
Add273
What do you do to convert kelvin into Celsius
Subtract 273
What is the kelvin temperature of gas directly proportional to
The average kinetic energy of its particles
What happens when gas particles collide in a sealed container
They exert as force as they are light but not massless
In a sealed container they smash against walls causing outward pressure
What does the outwards pressure of gas particles depend on
How fast the particles are going and how often they hit the walls
When a gas is at constant pressure what is the pressure and volume proportional to
Temperature
When the temperature of gas is at constant what does reducing the volume do
Particles get more squished and hit walls more often and pressure increases
Pressure and volume are
Inversely proportional
What is the relationship between volume and pressure when a gas of fixed mass is at a constant temperature
V1P1=V2P2
How does an investigation using a gas syringe show volume and temperature at constant pressure
Half fill with gas and seal with rubber bung
Heat up causing gas to expand pushing plunger outwards-volume of gas increase as temp increases
Pressure stays same as plunger free to move
Cool, gas contact and plunger pulled in
How to use a gas syringe to show pressure and volume at a constant temperature
Attach gas syringe half filled with air to pressure sensor
Push plunger on, compress gas and reduce volume
Increasing gas pressure (more collisions with walls)
Pull plunger out, increase volume and decrease pressure
Why are gases used for medicine kept under high pressure and how
Have valve to adjust flow rate
Pressure inside must be higher than outside to ensure high flow rate (outside is 1atm) if equal wouldn’t empty completely flow rate would remain zero and gas would stay inside canister
High pressure means lots of gas stored in small volume
Why do canisters holding gas need to be strong and give examples of materials
To hold the gas at high pressures without buckling or splitting
(Steel, carbon reinforced aluminium)
Size materials and pressures depend on what are where used for
What is flow rate of gas
The volume of gas per unit time released from a gas bottle
What is the kinetic theory of solids
Strong forces of attraction between particles, close together and fixed in regular arrangement
Not much energy, vibrate in fixed positions
