In the crystal of graphite, each carbon atom is covalently bonded to ... other carbon atoms arranged tetrahedrally around it.
One.
Two.
Three.
Four.
Grapgihte is a conductor of electricity because:
There are no free electrons in its crystal lattice since all of the four valence electrons are used in bonding.
There are free electrons in its crystal lattice since all of the four valence electrons are not used in bonding.
There are no free electrons in its crystal lattice since all of the five valence electrons are used in bonding.
There are free ions in its crystal lattice since all of the four valence electrons are not used in bonding.
The hardest natural substance ever known is:
Graphite.
Diamond.
Carbon.
Sulphur.
The allotropes of carbon are:
Amorphous carbon.
All are correct.
... is the existence of an element in two or more forms but in the same physical state.
Allotropes.
Polymorphism.
Isotopy.
Allotropy.
