Silicon dioxide, diamond, graphite

Question 1

describe bonding in silicon dioxide

Answer 1

strong covalent bonds between O and Si atoms - each Si bonded to 4 O atoms - formula is SiO2

Question 2

properties of diamond and carbon

Answer 2

strong covalent bonds between all atoms (diamond, each is bonded to 4 others, graphite each is bonded to 3) - both are giant covalent (graphite is in layers [malleable, as layers slide]) - very high M/BP strong covalent bonds - graphite conducts electricity (each atom has spare delocalised electron, forms electron cloud, free to move throughout structure) - diamond cannot