Chapter 5 Solids, Liquids, Gases Flashcards
In solids, attractions dominate ____
motion
In liquids, ____ is/are stronger
attractive forces
gases have no ___ or ___
fixed volume, fixed shape
melting point is the same as ___
freezing point
vaporization
the process of a liquid becoming a gas
condensation
process of a gas becoming a liquid
boiling point
temperature at which particles of liquid escape to form a gas
sublimation
solid changes direction from a solid to a gas (i.e. dry ice at room temp)
deposition
gas changes directly to a solid
a substance at low pressure and high temperature is probably a
gas
crystalization
liquid becoming a solid
ionic solids have ___ melting point
high
molecular solids have ___ melting point
low
sugar, aspirin, ice
intramolecular forces
attractive forces between atoms within a molecule, including ionic and covalent
how to know if hydrogen bond
F, O, or N bonded to H plus a lone pair of electrons (draw lewis structure)
how to know if dipole-dipole interaction
one polar molecule interacting with another polar molecule
london dispersion re: nonpolar molecules
nonpolar molecules ONLY have london dispersion
strongest intermolecular force
hydrogen
intermolecular force with intermediate strength
dipole-dipole
intermolecular force with least strength
london dispersion
larger molecules have ____ london dispersion
stronger london dispersion
anything made of just carbon and hydrogen is _______ (polar/nonpolar)
nonpolar, so only london dispersion
surface tension
energy required to increase the surface area of the liquid, stronger intermolecular force –> more surface tension
viscosity
resistance of a liquid when it flows (dependent on intermolecular forces and shape)
weak intermolecular forces –> low/high vapor pressure
high, because low boiling point means more gas –> more pressure
(gas) pressure =
force / area
normal atmospheric pressure in P and kPa
- 01325 x 10^5 Pa
101. 325 kPa
normal atmospheric pressure in atm
1 atm
normal atmospheric pressure in mmMg and torr
760 mmMg
760 torr
normal atmospheric pressure in bar
1.01325 bar
velocity _____ as molar mass increases
decreases
Boyle’s law
at constant temp, vol of gas is inversely proportional to its pressure.
Charles’ Law
at constant pressure and constant moles, the volume of a gas is directly proportional to its absolute temperature (K)
Gay-Lussac’s Law
for a fixed amount of gas at constant volume, pressure is directly proportional to absolute temperature (K)
Avogadro’s Law
at fixed temperature and pressure, volume of gas is directly proportional to the amount of gas (more gas takes up more space)
equation for combined gas law
if a variable is constant, cancel it out and solve for the equation remaining
If variables aren’t changing, which gas law and equation do we use? What unit does each variable need to be in?
Ideal gas law PV=nRT P in atm V in L n in mol (R is a constant) T in K
What is R?
ideal gas constant
0.0821
What are standard temperature and pressure?
273.15 K
1 atm
phase diagram - which is liquid, gas, and solid?
What’s the approximate melting point at 5 atm?
What’s the approximate boiling point at 2 atm?
about 115 degrees Celcius
What phase change is taking place from A–>B
vaporization (liquid changes into gas)
These properties are directly related to the strength of intermolecular forces
This property is inversely related to the strength of intermolecular forces in liquids
vapor pressure
Which is the only gas law that is inversely related and also non-linear
Boyle’s Law
