lesson 4 Flashcards
what is enthalpy of vaporization?
the energy needed to vaporize 1 mole of a liquid.
vaporization is ……
endothermic.
what is vapor pressure?
the pressure of vapor when vaporization and condensation are in equilibrium.
when is a system at equilibrium?
when no net change happens
factors that affect vapor pressure.
size of intermolecular forces,
temperature.
how does intermolecular forces affect vapor pressure?
the stronger the force the lower the pressure.
how does temperature affect vapor pressure?
as temperature increases, vapor pressure increases,
Clausius–Clapeyron Equation
ln ( P1 / P2) = Hvap / R * (1/T2 - 1/T1)
what is phase diagram?
diagram used to represent phases of a substance as a function of temperature and pressure.
in a phase diagram, what is a triple point?
the point at which all phases meet in a state of equilibrium.
what is critical point?
critical temperature and critical pressure.
what is critical temperature?
once a vapor reaches above that temperature. it can’t be liquified.
critical pressure?
the pressure required to liquify a vapor.
phase equilibrium lines?
the line between phases.
normal melting point?
the temperature where liquid and solid have the same vapor pressure.
