Covaent Bonding Flashcards
Definition of covalent bonding
The electrostatic attraction between protons in two nuclei and a shared pair of electrons between them
how strong are covalent bonds
covalent bonding is a very strong attraction
properties of simple molecular substances like c60 fullerene
low boiling point
don’t conduct electricity
why do simple molecular substances have low boiling points
- although simple molecules contain very strong covalent bonds there are also weak IMFs between the molecules
- when simple molecular substances boil its the weak IMFS which break
as molecular mass increases, what happens to the boiling point of simple molecular substances
as molecular mass increases so does the strength of the weak IMFs resulting in the boiling point increasing
why dont simple molecular substances conduct electricity
- electrical conductivity require charged particles that can move freely
- but in simple molecular substances there aren’t any charged particles
- simple molecular substances never conduct electricity because molecules are neutral
what is C60 fullerene
- c60 fullerene is a unique simple molecule composed of 60 carbon atoms in a ball
what is c60 fullerene boiling point like
its boiling point is low, but not as low as other molecules because of its high molecular mass
why is c60 fullerene soft and slippery
because the molecules can role over eachother easily
why is c60 fullerene an electrical insulator
because the molecules are neutral
give 3 examples of giant covalent substances
diamond
graphite
silicon dioxide
what is diamond
a form of pure carbon arranged in a giant lattice
descibe the stricture of diamond
- every carbon makes 4 covalentbonds
- tetrahedal shape
- ## strong grid like arrangement
why does diamond sublime at very high temperatures
- covalent bonds are very string
- there are lots of bonds in a giant lattice
- lots of energy is required to break all the bonds
what is diamond used for
cutting
why is diamond one pf the hardest substances
covalent bons are very strong
there are lots of bonds in a giant lattice
lots of energy is required to break all the bonds
why is diamond used in cutting
becuase its one of the hardest substances
can diamnond conduct electricity
no
why cant diamond conduct electricity
becaise all the atoms are neutral and all the elctrons are stuck inside an atom or a bond
what is graphite
a form of pure carbon arranged iunto a different giant lattice
describe the structure of graphite
layers of hexagons of carbion atoms
every caron makes 3 covalent bonds
weal IMFs between layers
delocalised electrons between layers
why does graphite sublime at very hugh temperatures
covalent bonds are very strong
there are lots of bonds in the giant lattice
lots of eery is required to break all the bonds
what is graphite used as
a solid lubricant in pencils
why is it used as a solid lubricant in pencils
because it is soft and slippery
why is graphite soft and slippery
because the layers can slide easily over each other
does graphite condi8ct electricity
yes
why does graphite conduct electricity
because inside the layers delocalised electrons can move freely
what giant covalent structure is silicon dioxide similar to
diamond
why is silicon dioxide similar to diamond
because of tis similar bonding and structure
describe the structure of silicon dioxide
every si makes 4 covalent bonds
every o makes 2 covalent bonds
tetrahedral shape
strong grid like arrangement
