bonding, structure & properties of matter Flashcards
solid
- regular arrangement
- very close together
- vibrate around fixed positions
liquid
- random arrangement
- close together
- flow around eachother
gases
- random arrangement
- further apart
- quick in all directions
changing states:
- particles stay the same
- way the particles arranged changes
- way particle move changes
melting boint:
melt & freeze at specific temperature
boiling point:
boil & condense at specific temperature
chemical bonds:
- ionic bonds
- convalent bonds
- metallic bonds
ionic bonding
transfer of electrons from
metal atoms —> non-metal atoms
ionic compounds are
giant structures of ions
ionic compounds held together…
by strong forces of attractions
ionic compounds:
-have high melting + boiling point
-do not conduct electricity when:
solid (ions can’t move)
molten
in solution
convalent bond
shared pair of electrons between atoms
convalent bond occurs in:
- non metallic elements (O2)
- compounds of non-metals (SO2)
in order for a covalent bond to bond:
- an electron from each atom is shared
- each atom has a complete outer shell
small molecules
contain a relatively small n of non-metal atoms joined together by convalent bonds
molecules=
- no overall electrical charge (can’t conduct electricity)
- usually have low melting & boiling points (weak intermolecular force)
larger molecules:
stronger intermolecular force
high melting and boiling point
giant convalent bonds:
high melting & boiling points
diamond
form of carbon
- strong convalent bonds
- does not conduct electricity
graphite
form of carbon
- giant convalent structure
- hexagonal structure
- weak intermolecular forces
graphene
a form of carbon, single layer of graphite
- hexagonal structure
- one atom thick
- very strong
- good thermal + electrical conductor
- nearly transparent
fullerenes:
- contain different n of carbon atoms
- hollow shapes
fullerenes can be used:
- to deliver drugs in body
- in lubricants
- as a catalyst
- reinforcing materials (tennis racket)
polymers
- very large molecule
- held together by strong convalent bonds
- intermolecular force = strong
- cheap + strong
plastics=
man made polymers
polymers=
used to make plastic bottles & bags
metallic bonding occurs in:
- metallic elements (iron & copper)
- alloys (stainless steel)
metals=
- giant structure
- electrons in outer shell are delocalised
delocalised
not bound to 1 atom
metallic bond
attraction between positive ions + delocalised electrons
properties for metals
delocalised electrons
delocalised electrons
move freely & transfer energy
—> makes metal good thermal & electrical conductors
copper:
unreactive metals (doesn’t react with water) easily shaped
copper uses
- electrical wiring
- water pipes
- saucepans
copper properties
ductile, malleable, good conductivity
aluminium uses
- high voltage power cables
- furniture
- drink cans
- food foil wrap
aluminium properties
- corrosion resistant
- ductile
- good conductivity
- malleable
- low density
what are alloys?
mixtures that contain a metal and at least 1 other element
alloys=
usually stronger & harder than pure metal
gold uses
- jewellery
- electrical junctions
gold properties
- ductile
- shiny
- good conductivity
