Changes

====Laboratory preparation====

====Laboratory preparation====

Members may be prepared in the laboratory by the heating anhydrous sodium ethanoate with an alkali e.g soda lime. (preparation of methane)<ref name=chemguide>[http://www.chemguide.co.uk Chemguide]</ref><ref name=NSC>Ababio, O. Y., New school Chemistry</ref>

Members may be prepared in the laboratory by the heating anhydrous sodium ethanoate with an alkali e.g soda lime. (preparation of methane)<ref name=chemguide>[http://www.chemguide.co.uk Chemguide]</ref><ref name=NSC>Ababio, O. Y., New School Chemistry</ref>

===Alkenes===

===Alkenes===

They are aliphatic homologous series of hydrocarbon which form unsaturated hydrocarbon. They have the general molecular formula CnH2n were n are positive integers. These compounds are unsaturated becaue they contain carbon-carbon double bonds where the two carbons are bonded together by one pi bond and one sigma bond, .each of the member of alkene has and SP2 hybridized orbital with a trigonal shapewith a bond angle of 120 degree given a total of 33.333% S-orbital character and 66.66% P-orbital character respectively. Alkenes undergo reactions such as Addition( hydrogenation, halogenation, hydrohalogenation) reactions, oxidation reaction,polymerization condensation reaction and elimination(convertion of alkene to alkyne) reactions respectively.  

Alkenes are aliphatic homologous series of hydrocarbon which form unsaturated hydrocarbon. They have the general molecular formula CnH2n, where n are positive integers. These compounds are unsaturated because they contain carbon-carbon double bonds where the two carbons are bonded together by one pi bond and one sigma bond. Each of the member of alkene has and SP2 hybridized orbital with a trigonal shape with a bond angle of 120°, given a total of 33.333% S-orbital character and 66.66% P-orbital character respectively. Alkenes undergo reactions such as Addition( hydrogenation, halogenation, hydrohalogenation) reactions, oxidation reaction,polymerization condensation reaction and elimination (conversion of alkene to alkyne) reactions respectively.  

Members include ethene 2 -carbons, butene 4 -carbons, pentene 5- carbons e.t.c.

Members include ethene 2 -carbons, butene 4 -carbons, pentene 5- carbons, etc.

====Laboratory preparation====

====Laboratory preparation====

Members may be prepared by dehydrating alcohols. E.g dehydrating ethanol with concentrated sulphuric acid gives ethene. Other members can be prepared in similar way but with corresponding higher molecular mass alcohol.<ref name=chemguide /><ref name=NSC />

Members may be prepared by dehydrating alcohols. E.g., dehydrating ethanol with concentrated sulphuric acid gives ethene. Other members can be prepared in similar way but with corresponding higher molecular mass alcohol.<ref name=chemguide /><ref name=NSC />

===Alkynes===

===Alkynes===