C3 states of matter Flashcards
particle arrangement solid
closely packed together
vibrate around fixed positions
liquid PA
close together
can slide over each other
move in random motion
gas PA
usually lots of space between them
move around randomly
particle model limitations
assumes particles are perfect sphere
doesn’t show intermolecular forces
ionic bonding
usually formed from reactions of metals with non metals
positive (metal) ions and negative (non metal) ions hold compound together with very strong forces of attraction- acting in all directions (between oppositely charged ions)
ionic compounds
bonds require lots of energy to break
high M + B points
solids at room temp
conduct electricity when molten or dissolved- delocalised electrons become mobile so can carry charge
covalent bonds
non metals sharing electrons
each shared pair is a covalent bond
simple molecules
low m + b points
weak intermolecular forces
no overall charge- cannot carry charge
graphite
layers of covalently bonded carbon atoms
no covalent bonds between layers
soft and slippery
conduct heat and electricity as electrons move along layers
fullerene structure
form cage like structures and tubes
based on hexagonal rings of carbon atoms
fullerene uses
transport methods for drug to specific body sites
catalysts
reinforcement for composite materials
graphene
single layer of graphite
one atom thick
v good electrical conductor
metallic bonding
positively charged metal ions
held together by electrons in outermost shell of each atom
delocalised electrons free to move throughout lattice
metal properties
bent and shaped- layers can slide over each other
alloys harder- different size atoms mean layers don’t slide over each other as easily
conduct heat + electricity due to dlclsd electrons
nanoparticle advs
high sa: v ratio
more atoms exposed at surface
means smaller quantities are needed
( catalysts in industrial processes)
