Alkanes and alkenes
 

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Alkanes C_nH_2n+2

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Alkane " halogenoalkane
Reagents: chlorine or bromine
Conditions: in the presence of ultraviolet light

CH₄ + Br₂    →   CH₃Br + HBr

Further substitution occurs in succeeding reactions:

CH₃Br + Br₂ → CH₂Br₂ + HBr

CH₂Br₂ + Br₂ →  CHBr₃ + HBr

CHBr₃ + Br₂ →  CBr₄ + HBr

Arenes
Halogenoalkanes
Alcohols
Aldehydes and ketones
Carboxylic acids
Acyl chlorides
Amines
Nitro compounds
Nitriles
Amides

Alkane + oxygen "  carbon dioxide and water, and heat.
Conditions: ignite in air or oxygen.

The general reaction for any alkane containing n carbon atoms is

C_nH_2n+2  +   ˝(3n + 1)O₂ →  nCO₂  +  (n +1)H₂O

Alkenes C_nH_2n

Alkene → 1,2-dihalogenoalkane
Reagents: chlorine or bromine                    
Conditions: in gas phase or in an inert solvent such as CCl₄ at r.t.:

CH₃CH=CH₂ + Br₂ → CH₃CHBr – CH₂Br

Alkene → halogenoalkane
Reagents: hydrogen halide
Conditions; in gas phase or in an inert solvent such as CCl₄ at r.t

Addition is according to Markovnikov’s rule, i.e. d⁺ goes to the carbon in the double bond bearing most hydrogen:

CH₃CH=CH₂ + HBr " CH₃CH(Br) – CH₃

Note that Markovnikov's Rule is not an explanation; explaining the orientation requires a knowledge of the mechanism and of the ease of formation of the intermediate carbocations.

Alkene → alkyl hydrogen sulphate
Reagents: concentrated sulphuric acid                                
Conditions: at r.t.

CH₃CH=CH₂ + HOSO₂OH → CH₃CH(OSO₂OH) -CH₃

Alkene → bromoalcohol
Reagents: bromine water                                                  
Conditions: at r.t.

The Br atom is the more positive end of the reagent:

CH₃CH=CH₂ + BrOH → CH₃CH(OH) - CH₂Br

Alkene " 1,2-diol
Reagents: potassium manganate(VII) solution made alkaline with sodium hydroxide               
Conditions: r.t.

The oxidising agent can be shown as [O]:

CH₃CH=CH₂ + H₂O + [O] → CH₃CH(OH) - CH₂OH