Combustion Of Alkanes Flashcards
What are the rules for balancing combustion equations ?
1)balance carbon first
2) balance hydrogen second
3)balance oxygen third
4)you can use half numbers
What is complete combustion?
Plentiful supply of oxygen
What are the products of complete combustion?
Carbon dioxide and water
What is incomplete combustion?
Limited supply of oxygen
What are the products of incomplete combustion?
Carbon monoxide
Water
What are the pollutants that pollute the atmosphere?
Sulfur dioxide
Particulates
Unburnt hydrocarbons eg methane
Carbon monoxide
Carbon dioxide
Nitrogen oxides
Water vapour
How is sulfur dioxide formed ?
Produced from the combustion of sulphur containing impurities in crude oil
S+O2 ->SO2
How are particulates formed?
Incomplete combustion of a fossil fuel
CH4 +O2-> C+ 2H20
How are unburnt hydrocarbons formed?
Hydrocarbons that aren’t burnt
How is carbon monoxide formed?
Incomplete combustion of a fossil fuel
CH4 +3/2O2-> CO +2H2O
How is carbon dioxide formed?
Complete combustion of a fossil fuel
CH4+2O2-> CO2 +2H2O
How is water vapour formed?
Complete and incomplete combustion
What are the harmful effects of SO2?
Combine with water vapour and oxygen in the atmosphere to form sulfuric acid
Results in acid rain and damages lakes fish,plant life and buildings
What are the harmful effects of SO2?
Combine with water vapour and oxygen in the atmosphere to form sulfuric acid
Results in acid rain and damages lakes fish,plant life and buildings
What are the harmful effects of particulates?
Can cause asthma
Carcinogenic
Global dimming
What are the harmful effects of unburnt hydrocarbons?
Greenhouse gas and form photochemical smog
What are the harmful effects of carbon monoxide?
Prevents oxygen from binging to haemoglobin so is toxic to humans
What are the harmful effects of carbon dioxide ?
Greenhouse gases
What are the harmful effects of nitrogen oxides ?
Nitrogen oxides combine with water vapour and oxygen in the atmosphere to form nitric acid and form photochemical smog
What are the harmful effects of water vapour ?
Greenhouse gas
How is sulphur removed from coal or natural gas?
At the power station CaCo3 thermally decomposes at high temperatures
At the power station sulphur dioxide reacts with CaO at high temperatures
What are catalytic converters?
Convert the pollutants carbon monoxide,nitrogen oxides and unburnt hydrocarbons into less harmful carbon dioxide nitrogen and water
How do catalytic converters work?
Use a catalyst such as platinum or rhodium the metals are coated onto a honeycomb shaped certain material because increases surface area of catalytic
What is the catalytic converter equation?( reaction between carbon monoxide and nitrogen monoxide to form nitrogen and carbon dioxide )
2CO +2NO -> N2 + 2CO2
What is the catalytic converter equation ?( reaction between unburnt HCs and nitrogen carbon dioxide and water
C8H18+25NO-> 2.5 N2+ 8CO2 +9H2O
What is global warming?
Global warming is an increase in the average temperature of the earth
What are greenhouse gases?
Water CO2 and CH4 are molecules which absorb IR and re emit it causing the earth to warm up
What is the greenhouse effect ?
When greenhouse gases trap heat
