SC7b Allotropes of Carbon Flashcards
what is an allotrope?
an allotrope is a different structural form of an element
giant structure of graphite
~layered structure with weak forces of attraction between the layers
~high melting point because strong covalent bonds need lots of energy to be broken
~conducts electricity as it has delocalised electrons that are free to move
what is graphite used in and why? 2
~lubricant due to weak forces of attraction between layers
~electrodes as it can conduct electricity
what are the carbon atoms like in graphite?
each carbon atom is only connected to 3 other carbon atoms
giant structure of diamond?
~very HARD because all carbon atoms are joined with strong covalent bonds
~HIGH MELTING POINT as the strong covalent bonds need lots of energy to be broken
~does NOT CONDUCT ELECTRICITY as it has no free charged particles.
what is diamond used in and why?
~cutting tools as it is very hard
DO NOT SAY JEWELLERY
how are carbon atoms connected in a diamond?
each carbon atom is connected to 4 other carbon atoms
properties of graphene (3)
~Very low density as the sheets are just 1 atom thick
~Very strong material as it contains covalent bonds
~Good electrical conductor as it has free electrons
properties of fullerene?
~LOW MELTING POINTS due to weak intermolecular forces between the molecules
~Soft and slippery substances due to WEAK INTERMOLECULAR FORCES between the molecules
~Individual molecules are STRONG due to the covalent bonds holding the atoms together
how are carbon atoms joined in fullerene?
each carbon atom is only connected to 3 other carbon atoms
What type of bonding is between the atoms in a molecule of water?
covalent
What type of structure does water have?
simple molecular
What strength of forces are there between different molecules of water?
weak
Does pure water conduct electricity?
no
Which element can exist as diamond, graphite and fullerenes?
carbon
