4.1 Covalent bonding Flashcards
what is the definition of covalent bonding
the electrostatic attraction between a bonded positive nuclei and a shared pair of electrons.
how would you describe covalent bonding
Very strong
what is a small group of atoms held together by covalent bonds called
Simple Molecule
what kind of boiling points do Simple molecular substances have
Low boiling points
Why do molecular substances have low boiling points
because they have weak intermolecular forces between molecules, which are easy to break.
Can Simple molecular substances conduct electricity
No
Why can’t simple molecular substance conduct electricity
Because the substance are neutral and can not carry charge.
not free to move
what happens as the molecular mass increases
the strength of the weak IMFs this results in the boiling point increasing
what is c60 Fullerene
c60 Fullerene is a unique molecule composed of sixty carbon atoms in a ball
Does c60 have a high Melting/boiling point and state a reason why
yes- because it has a larger molecular mass meaning stronger intermolecular forces which require more energy to break.
what is Diamond
Diamond is a form of pure carbon arranged into a giant lattice
Describe the structure of diamond
-Every c makes 4 covalent bonds
-Tetrahedral shape
-Strong, grid-like arrangement
does diamond sublime at a high temp if so why.
covalent bonds are very strong
it has Lots of bonds in the giant lattice
lots of energy is required to break all the bonds
what is diamond used for
cutting
because it is one of the hardest substances
can diamond conduct electricity if yes/no state why.
No it can’t beause it doesn’t have any freely moving particles and can not carry charge.( all its atoms are neutral)electrons are stuck inside an atom.;
what is a graphite
a pure carbon arranged in a different giant lattice
describe the structure of graphite
-Layers of hexagons of c atoms
-every c makes 3 covalent bonds
-weak intermolecular forces between layers
-delocalised electrons inside each layer
does graphite sublime at a high temperature
yes because it has lots of strong covalent bonds in the giant lattice
which require a lot of energy to break
what is the texture of Graphite and why
soft and slippery
layers that can slide easily over each other
used as a solid lubricant
what is graphite used for
A solid lubricant
can graphite conduct electricity and why
yes because it has delocalised electrons which are free to move and carry charge
what structure does silicon dioxide have
giant covalent structure
describe the structure of silicon Dioxide
every Silicon makes 4 covalent bonds
every oxygen makes two covalent bonds
Tetrahedral shape ( like diamond )
strong grid-like arrangement
what is silicon dioxide similar to
diamond
ionic bonding is between which two elements
metal + non-metal
what is the structure for ionic bonding
Giant lattice
Covalent bonding is between which elements
only non-metal
what is the structure of a covalent bonds
Simple molecules
metallic boning is between which elements
only metals
what is the structure of a Metallic bond
Giant lattice
what are properties of Ionic bonds
Brittle
usually soluble in water
High MP/BP
insulator when a solid
Conductor when a liquid
conductor when an aqueous
what are properties of Covalent bonds
Low MP/BP
Insulator
usually insoluble in water
Dull
what are properties of Metallic bonds
High MP/BP
Conductor
Malleable
Shiny
