structure and bonding Flashcards
Traits of solids
Very packed together
Cannot flow freely
Can vibrate
Fixed space
Hard to compress
Traits of liquids
Not much space between
Hard to compress
Flow freely
Take shape of their container
Traits of gases
Widely spaced
Easy to compress
Moves quickly and randomly
What has to be given to a solid to be a liquid
Energy so it can break the forces of attraction and move freely as a liquid
Stronger the forces of attraction…
More energy needed to be put it, higher melting/ boiling point
Limitations of a single particle model
Particles are not a solid sphere
Particles have forces between them
metals make..
positive ions
non metals make…
negative ions
what is ionic between
a metal and a non metal
what do ionic compounsds form
giant lattice structures
properties of iomic compounds
very strong electrostatic forces of attraction
very high melting and boiling points
cant conduct whilsta solid
diagram to show ionic bonding
dots and crosses
ionic compound in solution
does conduct
ions can become mobile when separated by water
molten ionic compound
does conduct
high temps overcome the strong force
ions can move
what is coveylant bonding between
two non metals
what happens in coveylant bonding
the two atoms share a pair of electrons, each pair shared is asingle coveylant bind.
dif types of bonding models
dot and cross
stick bonds
ball and stick
why are smaller coveylant molecules so volatile
because the bond between each bond is very tight however the intermoleculaar force is weak, meaning they are easy to overcome with a raise in temp.
larger the size of the molecule the stronger the forces are
do covelylant compounds conduct
no not even as a liquid because there is no electrical charge/ electrons are shared so none are free
unless theyre reacted w water or molten
properties of giant coveylant structures
high m and b points
insoluable
hard and dont condutc except graphite
formation of diamond
each carbon atom is bonded to 4 others in a huge huge structre
why cant diamond/ silicon di conduct
all the electrons are bonded so there are no electrons free to conduct
formation of silicon di
silicon and oxygen bonded
formation of graphite
carbon atom bonded to three other carbon atoms
properties of graphite
high m and b point
soft and slippery
v good conductor
why is graphite slippery
the bonds are very strongly bonded but they are in layers that are weakly joined so they can easily slide
why is graphite a strong conductor
because only three elctrons are bonded there is one delocalised electron that can move freely and conduct
why is graphite similar to metal
good conductor of electricity
have delocalised electrons
whats a fullerene
carbon atoms bonded together in shexagons or pentagons that makes huge hollow shapes
what is nanotubes
large cylinder fullerenes
properties of nanotubes
very strong and bendable
very strong conductor because its bonded like graphite
uses of fullerenes
delivery of pharmacuticals into body because of cage structure
lubricants- slippery
catalysts- high SA/V ratio
what is graphene
a single atom thick layer of graphite
uses of graphene
very good conductor
very strong so can be used for computers and electromics- like a 2d screen
what are metal structures like
huge lattice of pos ions as the outer layer of electrons are delocalised and move throughout
the pos ions are very compact and regularly arranged
what bonds the metal lattice
strong atraction between the positively charged ions and the neg electrons that move
why are metals easily bent
the atoms are in layers that can slide
what are alloys and what do they do
a mixture of metals that are larger sp they distort the layers and block them from sliding. makes them harder than pure metals
uses of metal
cooking stuff because it conducts thermal energy and melts high
wires because it conducts electricity
properties of metals
high melting and boiling points bc the electrons can move and hold the pos ions
greeat conductors becasue of delocalised electrons
ductile because layers can slide
how do ionic structures work in a liquid for electrolysis
the water molecules have enough enrgy to dissolve them, leaving them free to move and marry their charge- which are attracted to the oposite anode/ cathode
what are macromolecules
giant coveylant structures
whats an electrostatic force
the force of attraction between pos and neg ions that hold them toegther, as well as the force between protons and electrons in an atom
whats an allotrope
substances made from the same element in the same state with dif structures eg graphite and diamond
whats a polymer
large molecule made up of lots of smaller units called monomers
