5.1 States of Matter
______ have a fixed shape and volume.
Solids
True or false: Ideal gases are real.
False
A solid changes to a liquid at its _______ _____.
melting point
What do we call the regularly repeating arrangement of ions, atoms or molecules?
a crystal lattice
What are allotropes?
different crystalline forms of the same element
_____ have no fixed shape or volume.
Gases
Name one assumption of the kinetic theory of gases.
Possible answers:
gas molecules move rapidly and randomly
the volume of the gas molecules is negligible
no IMFs of attraction or repulsion between gas molecules
all collisions are elastic
the temperature of the gas is related to the average kinetic energy of the molecules
True or false: When a solid is heated, the forces of attraction between the particles weaken.
True
Ionic compounds have ____ melting points and boiling points.
high
Particles between 0.1 and 100 nanometres are called _____________.
nanoparticles
______ particles have limited movement from place to place, in all directions.
Liquid
The volume that a gas occupies depends on its ________ and its ___________.
pressure, temperature
What is the phase change of freezing?
liquid to solid
Name three physical properties of metals.
Possible answers: good conductors of electricity, malleable, ductile, high density, etc.
The shape of buckminsterfullerene can be compared to the shape of what?
a football
_____ particles can only vibrate.
Solid
What is the ideal gas equation?
pV = nRT
Define enthalpy change of vaporisation.
the energy required to change one mole of liquid to one mole of gas
The ionic lattice for sodium chloride is cubic. In sodium chloride, each sodium ion is surrounded by ___ oppositely charged chloride ions.
Why does buckminsterfullerene have a relatively low sublimation point?
There are weak intermolecular forces between each buckminsterfullerene molecule and no continuous layered giant structure
Gas particles are far apart, thus gases can be __________.
compressed
Calculate the number of moles (n) of a gas sample that occupies a volume of 25.0 dm3, at a pressure of 101.3 kPa and a temperature of 298K.
n = 1.02 mol
Define vapour pressure.
the pressure exerted by a vapour in equilibrium with a liquid
In graphite, the carbon atoms are arranged in ______ layers.
planar
State two characteristic physical properties of nanotubes.
Possible answers: high electrical conductivity along the long axis of the cylinder, very high tensile strength, and high melting point.