part 1 Flashcards
Enthalpy of combustion definition
energy transferred when 1 mole of fuel is burned completely in oxygen
Delta H for exothermic reactions
Delta H negative
Delta H sign for endothermic. reactions
Delta H positive
formation of oxides of sulphur
S in fuel reacts with 02 in air at high temp in engine
formation of oxides of nitrogen
N2 in air reacts with 02 in air at high temp in engine
formation of particulates
incomplete combustion of fuel
formation of unburned hydrocarbons
from fuel evaporating or not reacting
what produces and what are the primary pollutants
domestic sources and motor vehicles produce primary pollutants (NOX, CXHY and CO)
formation of photochemical smog
Photochemical smog is a mixture of pollutants that are formed when react to UV radiation. Forms ozone.
effects of photochemical smog
causes haziness and reduced visibility
eye/nose irritation
difficulty breathing
what do catalytic converters concert hydrocarbons and nitrogen monoxide to
unburned hydrocarbons are oxidised to C02 and H20
Nitrogen monoxide is reduced by carbon monoxide to Nitrogen and C02
What’s the catalyst in catalytic converters
Platinum
heterogeneous catalyst process
1) reactants adsorbed onto catalyst surface
2) intramolecular bonds in the reactants weaken and break
3) new bonds form to make the products
4) product diffuses away from the surface
catalyst poisons process
poisons become strongly adsorbed to the catalyst surface and prevent the reactants binding to the catalyst
electrophile definition
an ion or molecule that can form a covalent bond by accepting a pair of electrons
