1. Introduction
1.1. Unsaturated hydrocarbon, CnH2n+2
1.2. Triple bond
1.3. sp-hybridization
1.4. Nomenclature
1.4.1. -ane to -yne
2. Preparation in industry
2.1. Hydrolysis of Calcium Carbide
2.1.1. Reagent: Calcium Carbide, CaC2
2.1.2. Condition: Drip into water
2.1.3. Products: Ethyne and Calcium Hydroxide
2.1.4. CaC2(s) + 2H2O (l) --> Ca(OH)2 (s) + HC≡CH (g)
2.2. Pyrolysis of methane
2.2.1. Reagent: Methane gas, CH4
2.2.2. Condition: 1500-1600 °C
2.2.3. Products: Ethyne and Hydrogen gas
2.2.4. 2CH4(g) --(1500-1600°C)---> HC≡CH (g) + 3H2 (g)
3. Physical properties
3.1. Not soluble in water but soluble in organic solvent
3.1.1. Alkane is non-polar
3.2. Slightly higher boiling point compare to alkane and alkene
3.3. Similiar with alkanes and alkenes
4. Chemical properties
4.1. Combustion
4.1.1. Rapid oxidation reaction
4.1.2. Exothermic, only burn in gaseous state
4.1.3. General equation: CxHy +[x+ (y/4)] O2 ——>xCO2 + (y/2)H20
4.2. Addition reaction
4.2.1. Hydrogenation
4.2.1.1. Formation of alkanes
4.2.1.1.1. Reagent: H2 (gas)
4.2.1.1.2. Condition: Heat with Ni/Pd/Pt as catalyst
4.2.1.1.3. Product: Alkanes
4.2.1.2. Formation of alkenes
4.2.1.2.1. Reagent: H2 (gas)
4.2.1.2.2. Condition: Heat with Lindlar's catalyst, Pd/ (PbO, CaCO3)
4.2.1.2.3. Product: Alkenes
4.2.1.2.4. Produced from LIndlar's catalyst: Cis-isomers
4.2.1.2.5. Sodium dissolved in ammonia solvent (condition): Trans-isomers
4.2.2. Halogenation
4.2.2.1. Reagent: Cl2 or Br2 in CCl4
4.2.2.2. Condition: Room temperature or in the absence of light
4.2.2.3. Product: Haloalkanes
4.2.2.4. Observation: Reddish-brown (Br2)/ Greenish Yello (Cl2) is rapidlly decolourised
4.2.3. Hydration
4.2.3.1. Reagent: H20 (gas)
4.2.3.2. Condition: Heat at 60°C in the presence of HgSO4/H2SO4
4.2.3.3. Product: Alkenols or Carboxyl compounds (Aldehyde or Ketone)
4.2.3.4. Markovnikov's rules applied
4.2.4. Hydrohalogenation
4.2.4.1. Formation of Halogenoalkanes
4.2.4.1.1. Reagent: Hydrogen Halides (HX) (X= F/Cl/Br/I)
4.2.4.1.2. Condition: Room temperature
4.2.4.1.3. Product: Halogenoalkanes
4.2.4.1.4. Markovnikov's rules applied
4.2.4.2. Formation of Halogenoalkenes
4.2.4.2.1. Reagent: Hydrogen Halides (HX) (X= F/Cl/Br/I)
4.2.4.2.2. Condition: HgCl2
4.2.4.2.3. Product: Halogenoalkenes
4.2.4.2.4. Markovnikov's rules applied
4.3. Oxidation
4.3.1. Reaction with KmnO4
4.3.2. Reagent: Acidified or alkaline KMnO4
4.3.3. Condition: Cold
4.3.4. Observation: Purple of KMnO4 is decolorized and brown precipitate of MnO2 formed (only alkaline condition got brown ppt) (acid condition no brown ppt)
4.4. Substitution reaction
4.4.1. Only occured for terminal alkynes (tripal bond at ending)
4.4.2. Ammoniacal silver (II) solution, Ag(NH3)2+ / Ammoniacal copper (I) solution Cu(NH3)2+
4.4.3. White precipitate or reddish brown precipitate settled at the bottom