June 2009 P2 Q2 - Solution

2(a)(i)    Solid, liquid and gas.

2(a)(ii)   Melting point – A.

              Boiling Point – B.

2(a)(iii)  A mixture of water and ice.

2(a)(iv)  Water vapour to water – condensation.

              Iodine (s) to iodine(g) – sublimation.

2(b)(i)   An allotrope is a crystalline solid form of an element having a different   structure from

             another solid form of the same element.

2(b)(ii)  Conducts electricity – Graphite.

             Explanation – There are delocalised electrons in graphite.

2(c)(i)  Crude oil.

2(c)(ii)  Structural isomerism is the existence of compounds with the same   molecular formula 

             but different structural formulae.

butane

methylpropane