Silicon is a non-metal found in Group IV of the Periodic Table.

1. (a)Silicon is manufactured by the reduction of silicon dioxide with carbon. SiO2 + 2C → Si + 2CO What is the maximum mass of silicon that can be made from 300 g of silicon dioxide? mass of silicon ..................................................... g[2]
2. (b)Silicon has a giant molecular structure. Suggest two physical properties of silicon. 1 2[2]
3. (c)(i)Silane has the molecular formula SiH4. Draw the ‘dot-and-cross' diagram for silane. You only need to show the outer shell electrons of silicon.[1]
4. (c)(ii)Using ideas about structure and bonding, suggest why silane has a low boiling point.[2]
5. (d)(i)Siloxanes are condensation polymers. The partial structure of a siloxane can be represented as shown. CH3 CH3 CH3 CH3 -O-Si—O—Si —O—Si — O-Si- CH3 CH3 CH3 CH3 What is meant by the term condensation polymerisation?[2]
6. (d)(ii)Draw the repeat unit of this siloxane.[1]
7. (e)Butene forms an addition polymer called poly(butene). CH3 H₂C C C H H H butene Draw a partial structure for poly(butene). You must show at least two repeat units.[1]

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