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Organic chemistry A Chapter 2 Methane By Prof. Dr. Adel M. Awadallah Islamic University of Gaza. Bond Angles in Methane. Physical Properties of Methane Colorless gas, Nonpolar (London Forces) mp = -183, bp = -161.5 o C Only slightly soluble in water
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Organic chemistry A Chapter 2 Methane By Prof. Dr. Adel M. Awadallah Islamic University of Gaza
Physical Properties of Methane Colorless gas, Nonpolar (London Forces) mp = -183, bp = -161.5 oC Only slightly soluble in water Soluble in organic solvents Source Anaerobic decay of plants {{ Natural gas (97%) }}
Halogenation (vigorous reaction)F2 > Cl2 > Br2 >>> I2(no reaction) Control of chlorination Use excess methane and distill Methane bp = -161.5 oC Methyl chloride bp -24 oC
Inhibitors A substance that slows down or stops a reaction even though present in small amount.
Energy of Activation The minimum amount of energy that must be provided by a collision for reaction to occur.
Rate of Reaction A chemical reaction is the result of collisions of sufficient energy and proper orientation Rate = probability factor X Collision frequency X energy factor Collision frequency depends on concentration, size and temperature Probability factor depends upon geometry Energy factor depends upon temperature and activation energy (increasing temperature and decreasing Ea increases the rate of reaction) Rate = PZe-Ea/RT Assume Ea1 = 5 Kcal andEa2 = 10 Kcal Rate 1/ rate 2 = 100
Structure of the methyl radical , (planar , sp2 hybridization)
When Ea is small, TS resembles reactants When Ea is large, TS resembles products