Condensation and Evapouration Flashcards
Define Condensation
Gas turns to liquid
When a gas cools, the particles in the gas [ ] and lose kinetic energy. The attractive forces between the particles [ ].
slow down
pull them closer together
If the temperature gets [ ] enough and the gas particles get close enough together that condensation can take place, the gas becomes [ ]
cold
liquid
Water vapour in the air condenses when it comes into contact with [ ] eg, drink glasses
cold surfaces
Define Evapouration
When liquid turns to gas
Particles near the surface of a liquid can escape and become gas particles if: (2)
The particles are travelling in the right direction
The particles are travelling fast enough (they have enough kinetic energy) to overcome the Attractive Forces of the other particles in the liquid.
The [ ] particles (with the most kinetic energy) and most likely to evaporate from the liquid - so when they do, the average speed and kinetic energy of the remaining particles [ ].
fastest
decreases
This decrease in average particle [ ] means the temperature of the remaining liquid [ ] - the liquid cools.
energy
falls
The rate of evaporation will be faster if the… (4)
Temperature is higher
Density is lower
Surface area is larger
Airflow over the liquid is greater
Why does ‘Temperature is higher’ make evaporation faster?
the average particle energy will be higher, so more particles will have enough energy to escape
Why does ‘Density is lower’ make evaporation faster?
The forces between the particles will usually be weaker, so more particles will have enough energy to overcome these forces and escape the liquid.
Why does ‘Surface area is larger’ make evaporation faster?
more particles will be near enough to the surface to escape
Why does ‘Airflow over the liquid is greater’ make evaporation faster? (2)
The lower the concentration of an evaporating substance in the air it’s evaporating into, the higher the rate of evaporation
A greater airflow means air above the liquid is pep laced more quickly so the concentration in the air will be lower
What makes the rate of condensation faster? (4)
Temperature of the gas is lower
Density is higher
Temperature of the surface, the gas touches is lower
Airflow is less
Why does ‘Temperature of the gas is lower’ make condensation faster?
the average particle energy in the gas is lower, so more particles will slow down enough to clump together and form liquid droplets
