C3h-Allotropes of carbon and nanochemistry Flashcards
What are allotropes?
Different structural forms of the same element in the same physical state e.g theyre all solids
What is the structure of diamonds?
Each carbon atom form 4 covalent bonds in a very rigid giant covalent structure
What is the structure of graphite?
Each carbon atom forms 3 covalent bonds, creating sheets of carbon atoms which are free to slide over eachother
What is the structure of buckminster fullerene?
Molecules of carbon which are shaped like closed tubes or hollow balls
What are the physical properties of diamonds?
- lustrous, colourless and clear
- hard and has a high melting point
- insoluble in water
- does not conduct electricity
Why is diamond used in cutting tools and jewellery?
- diamond is really hard because of its very rigid giant covalent structure
- high melting point
Why does diamond not conduct electricity?
It has no free electrons or ions
Why is diamond hard and have a high melting point?
- hard because each of its carbon atoms form 4 covalent bonds in a very rigid giant covalent structure
- high melting points because strong covalent bonds take a lot of energy to break
What are the properties of graphite?
- black, lustrous and opaque
- slippery
- insoluble in water
- conducts electricity
Why is graphite used in pencil leads and lubricants?
- black
- opaque -shiny
- layers are sliplery and can be rubbed off easy because of the weakly held layers
Why do diamond and graphite have a giant molecular structure?
Carbon can form lots of covalent bonds with itself
What are the properties of giant molecular structures?
Because of the many strong covalent bonds, they are
- strong
- have a high melting point
- doesnt dissolve in water
Why dont most giant molecular structures conduct electricity?
There arent any free electrons or ions
Why are nanotubes used to reinforce graphite in tennis rackets?
Nanotubes are very strong.
What are nanotubes used as in electrical circuits?
Semiconductors
