structure and properties of giant covalent structures

what is the structure of a giant covalent structure?

millions of atoms join together by covalent bonding, forming what is (basically) one huge molecule.

how strongly bonded are the atoms in a giant covalent structure?

very strongly - unlike in a simple molecular structure where all the molecules are kept together by weak intermolecular forces, in a giant covalent structure all the atoms are covalently bonded to each other. covalent bonds are very strong.

what is true about the melting and boiling points of giant covalent structures?

they are very high

• due to both the strength of the bonds and the sheer amount of bonds in these structures, they require a lot of energy to overcome

what is hardness?

how resistant a material is to scratching 

note - not to be confused with strength, which is how well a material can keep its shape when a force is applied to it 

what is true about the hardness of giant molecular structures and why?

they are very hard

• there are many strong bonds in these structures, which means they are difficult to break (which needs to happen if a material is to be scratched) making it hard

what is true about the conductivity of giant covalent structures?

most cannot conduct electricity

• for a material to be able to conduct, it needs to have charged particles which are free to move through the structure

• since the structure is so rigidly held together by strong covalent bonds, there would be no free particles to move through the structure

• and since these bonds are covalent, there are no ions or charged particles which can move through the space in the first place

• therefore, most of these structures have neither of the two requirements needed to conduct electricity