Bonding, Structure and Properties of matter Flashcards
(24 cards)
what is an ion and how is it formed?
- it is a charged particle
- it is formed when an atom looses or gain electrons
what ions do metals form and non-metals?
METALS: positive
NON-METALS: negative
non-metal and metal form what type of bond?what type of force?
IONIC
- electrostatic
non-metal + non-metal form what bond?
COVALENT
- share electrons
eg. hydrogen (h2) oxygen (o2) chlorine (cl2)
- share electrons
what forms a simple molecular structure ?
a substance containing covalent bonds
what force is in a simple molecular structure?
intermolecular forces
they are quite feeble and are need to break in order to melt or boil (low mpt and bpt)
what is a macromolecule?
giant covalent structure
in a diamond how many covalent bonds does a carbon atom form?
FOUR
in graphite how many covalent bonds does a carbon atom form?
THREE
what are the properties of diamond?
- very hard
- strong covalent bonds so has a high melting and boiling point
- doesn’t conduct electricity as it has no free electrons or ions
properties of graphite?
- sheets of carbon atoms arranged in hexagons
- NO covalent bonds between layers
- soft and slippery
- has delocalised electrons so conduct heat and electricity
properties of graphene?
- it is a sheet of carbon atoms
- ONE ATOM THICK so it is two dimensional/light
- strong covalent bonds
- delocalised electrons so conducts heat and electricity
what is an allotrope?
different structural forms of the SAME ELEMENTS
eg. diamond, graphite and graphene
what is Fullerenes?
it is an allotrope of carbon shaped like a hollow ball
atoms arranged in hexagons, heptagons and pentagons
can trap other molecules in it
high surface area
makes lubricant
what is nanotubes?
- tiny carbon cylinders made by fullerenes
- they don’t break when stretched
- can strengthen materials without adding too much weight
what is involved in metallic bonding?
DELOCALISED ELECTRONS
ELECTROSTATIC ATTRACTION
why are metals good conductors?
because the delocalised electrons carry electrical current and heat through the whole structure .
what is an alloy?
a MIXTURE of TWO OR MORE metals
or a METAL and ANOTHER ELEMENT
why is an alloy harder than pure metal?
because the mixture has different sized atoms which will distort layers making it difficult for them to slide over each other
properties of solids:
- STRONG forces of attraction
- fixed position DON’T move
- particles VIBRATE about their position
- when heated : particles vibrate faster and expand slightly
properties of liquids:
- WEAK forces of attraction
- free to move past each other but stick close together
- don’t keep a definite shape
- moving in random motions
- when heated: particles move faster and liquids expand
properties of a gas:
- VERY WEAK forces of attraction
- free to move
- don’t keep a definite shape or volume
- move randomly
- when heated: particles move faster and they either expand or their pressure increases
what are the uses for nanoparticles?
- help make new catalysts
- nonomedicine
- electric circuits
- deodorants
- wound dressing
- cosmetics
negative aspects of nanoparticles ?
- the way they affect our body is not fully understood
