Evaporation and Vapor pressure

Evaporation and Vapor pressure

Evaporation and Vaporization

• These words are synonymous

• they are the term for the process in liquid molecules escaping the surface of the liquid and becoming a gas

Condensation

Condensation is the process of vapor molecules becoming a liquid.

Multiple Select

The process of going from liquid to gas

• evaporation

• vaporization

• condensation

• sublimation

Multiple Choice

The process of going from gas to liquid

• vaporization

• condensation

• evaporation

• sublimation

Vapor pressure

• the pressure of the vapor present at equilibrium with its liquid is called equilibrium vapor pressure, or more commonly, the vapor pressure of a liquid

• When the rate of evaporation and condensation are equal the system has reached equilibrium

Open Ended

What is dynamic equilibrium?

Vapor pressure continued

• Volatile liquids have high vapor pressures

• Volatile means they evaporate quickly

• The stronger the intermolecular forces the lower the vapor pressure

Multiple Choice

If a substance has weak intermolecular forces, it will have a relatively ______ vapor pressure

• high

• low

• average

Multiple Choice

Volatile liquids do what?

• explode

• look yellow

• are rare

• evaporate rapidly

The Relationship Between Boiling Point and Vapor Pressure

• In order for a liquid to boil the average kinetic energy of the liquid molecules must be great enough to produce a pressure that can oppose the atmospheric pressure pushing down on the liquid

• For water that temperature is 100 degrees Celsius at 1 atm

• If you are in an elevated area such as Leadville, Colorado the boiling point will be lower because the atmospheric pressure is lower

Open Ended

What affect does elevation have on boiling point