Exam 1 Flashcards
What does fusion mean
Melting
What does crystallization mean
Freezing
What does sublimation mean
When gas goes to solid
Intermolecular forces
Attractive forces between all molecules and atoms
What are the four types of intermolecular forces
- Dispersion Forces
- Dipole-Dipole Forces
- Hydrogen Bonding
- Ion-Dipole Forces
Dispersion forces (London forces)
An intermolecular force exhibited by all atoms and molecules that results from fluctuations in the electron distribution
Induced dipole
The temporary dipole established in one molecule, induces a temporary dipole on its neighboring atoms, which then attract one another
-more surface-surface contact = larger induced dipole = stronger attraction
-the straighter the shape = stronger dispersion force
Polar molecule
Has a permanent dipole
all polar molecules = dipole-dipole intermolecular forces
-has higher melting and boiling points than non polar molecules of similar molar mass
Dipole-Dipole forces
An intermolecular force exhibited by polar molecules that results from an uneven charge distribution
Hydrogen Bonding
Polar molecules containing H atoms bound directly to small and highly electronegative F, O, or N atoms bound directly
Ion-dipole force
Occurs when ionic compound is mixed with a polar compound
-stronger than other intermolecular forces
Surface Tension
The energy recruited to increase the surface area of a liquid by a unit amount
-tendency of liquids to minimize their surface area
Viscosity
The resistance of a liquid to flow
What is vaporization
Go from liquid to gas
-endothermic reaction
What is condensation
Go from gas to liquid
-exothermic process
Heat of vaporization
The amount of heat required to vaporize one mole of a liquid to gas (ALWAYS POSITIVE)
The rate of vaporization
Increases with
-increasing temperature
-increasing surface area
-decreasing strength of intermolecular forces
Vapor pressure
The pressure of a gas in dynamic equilibrium with its liquid
-rate of condensation equals rate of evaporation
Factors that affect vapor pressure of a liquid
- Intermolecular forces
- Temperature
Boiling point
of a liquid, its the temperature at which the liquids vapor pressure = external pressure
-the interior liquid molecules have enough energy to become gaseous
Normal boiling point
Of a liquid, the temperature at which its vapor pressure equals 1 atm
As intermolecular forces increase
Viscosity, Heat of Vaporization, Boiling point, and melting point: increase
Rather of vaporization, vapor pressure: decrease
Phase diagram
A map of the states of a substances as a function of pressure (y-axis) and temperature (x-axis)
Triple point
The three states are equally stable (coexist) and in equilibrium
Miscibility
The ability to mix without separating into two liquids
