giant covalent structures

Question 1

diamond

Answer 1

-high melting point - each carbon atom forms 4 strong covalent bonds
-very hard - needs a lot of energy to break the bonds
-can’t conduct electricity - no free electrons
-good conductor of heat - the strong bonds allow energy to transfer through the structure

Question 2

graphite

Answer 2

-high melting point - 3 strong covalent bonds
-soft - form layers which are held by weak forces so they can slide
-conducts electricity - delocalised electrons as there are only 3 covalent bonds
-good conductor of heat - there are free electrons

Question 3

silicon dioxide

Answer 3

high melting point - 4 strong covalent bonds to oxygen
hard - needs a lot of energy to break the bonds
-can’t conduct electricity - no delocalised electrons
-good conductor of heat - strong bonds allow heat to transfer through the structure