54-109 (jack) Flashcards
where r metals found in the periodic table
in the middle, to the left and along the bottom
charcteristics of metals (4)
structure (3)
other (1)
- delocalised electrons
- arranged in layers
- (most) high melting and boiling point
- can be bent and shaped as layers slide over eachother
why are metals good conductors of electricity
because the delocalized electrons can move freely and carry the charge through a substance
why are metals good conductors of heat
delocalised electrons transfer the thermal energy
what are alloys
mixture of a metal with other elements
why are alloys harder than regular metals
layers are distorted from the different types of partcles in them with the different elements
transision metals compared to group 1 (5)
transion metals are:
higher melting points
harder
stronger
more dense
less reactive
charcteristics of transition metals (3)
have ions with different charges
form coloured solids
useful catalysts
ionic bonding
non metal and metal
what are ionic compounds held together by
strong electrostatic forces between oppositely charged ions.
characteristics of ionic compounds
- form giant lattices
- high melting and boiling points
- when solid do not conduct electricity as ions not free to move
- when melted or dissolved they do conduct electricity as ions r free to move
covelent bonds
non metals sharing bonds
covelent bonds characteristics (6)
- strong bonds
- consist of small simple molecules
- usually gases or liquids
- low melting and boiling point
- have weak intermollecular forces between molecules
- do not conduct electricity as dont have an overall charge
polymers
very large covalent structures held together by strong covalent bonds
e.g. giant covalent structures (3)
silicone dioxide, diamond, graphite
giant covelent structures have…
high melting and boiling points
4 forms of carbon arrangement
- diamond
- graphene
- graphite
- fullerenes
diamond charcteristics (2)
- each carbon forms 4 covelent bonds
- very hard because of strong cov -bonds
-doesnt conduct elec as no delocalised electrons
characteristics of graphite (4)
- hexagonal rings with carbon being attached to 3 cov bonds
- layers r not bonded and can slide over each other
- can conduct elec as 1 electron from each carbon is delocalized and cam move between layers
- good heat conductor of heat for same reason
how thicks a layer of graphene
one atom
what does graphene do
conduct elec and is strong
what are fullerenes
molecules of carbon atoms with hollow shapes
formula for bucky ball
C60
carbon nanotubes have very high…
length to diametre ratio
