Alkanes/Haloalkanes Flashcards
Define Ozone
O3 in atmosphere - absorbs UV
Outline the danger of Holes in the Ozone
O3 decrease = increase UV & skin cancer
Define CFCs and outline their impact on Ozone
Chlorofluorocarbons - decrease in O3
Outline the 2 reactions of how CFCs reduce Ozone
- Cl* + O3 -> ClO* + O2
- ClO* + O3 -> Cl* + 2O2
Outline the overall reaction of CFC Ozone reduction
203 -> 3O2
Why is alkane combustion important?
Hi energy release
Outline Complete combustion
(Enough O2 present) X + O2 -> CO2 + H2O
Outline incomplete combustion
(Not enough O2) X+O2 -> CO+C+H2O
Outline the purpose of Catalytic converters
Removes CO & NOx (toxic)
Outline the process inside a catalytic converter
HC, CO, NOx (from air N2) + rhodium catalyst -> N2, H2O, CO2
Outline the danger of S impurities
H in H2O in atmosphere = H2SO4
What’s used in Flue Gas Desulfurisation?
CaO + gypsum
Identify the importance of Flue Gas Desulfurisation?
Pollutants -> global warming, H+ rain, health issues
Define Cracking
C-C-C-C-C-C -> C-C C-C C-C (more useful)
Outline the conditions and products of Thermal Cracking
Conditions: 1200K & 7000 kPa
Products: Mixture of CnH2n+2 & CnH2n
Outline the Conditions and Products of Catalytic Cracking
Conditions: 720K, Normal Pa, Zeolite catalyst
Products: Aromatic Compounds and C rings
Define Chlorination of Alkanes
Alkanes + Halogens ->(UV)-> Halogenoalkanes
Outline how Alkane Chlorination works
UV breaks down Halogen bonds -> Free Radicals & initiation, propagation & termination
Outline the Initiation in Chlorination (define and reaction)
Halogen broken down
Cl2 ->(UV)-> 2Cl*
Outline the 2 Propagation steps in Chlorination (define and both reactions)
H replaced and Cl* reformed as a catalyst
Cl* + CH4 -> *CH3 + HCl
CH3 + Cl2 -> CH3Cl + Cl