Alkanes-Combustion Flashcards
What is the equation for complete combustion of methane?
CH4 + O2 —->CO2 + H2O
What are the two equations for the incomplete combustion of methane?
CH4 +O2 —-> CO + H20
CH4 + O2 —-> C + 2H2O
Why does incomplete combustion happen?
If there is not enough oxygen in the reaction.
How is CO2 formed, what problems does it cause and how can we reduce the problem?
-Complete combustion of fuels containing carbon.
-It is a greenhouse gas.
-Try to burn less fossil fuels.
How is CO formed, what problems does it cause and how can we reduce the problem?
-Incomplete combustion of fuels containing carbon.
-It is toxic to humans.
-Ensure a good supply of oxygen when burning fuels.
How is carbon(soot) formed, what problems does it cause and how can we reduce the problem?
-Incomplete combustion of fuels containing carbon.
-Blackens buildings, causes respiratory problems and global dimming.
-Ensure a good supply of oxygen when burning fuels.
How is H2O formed, what problems does it cause and how can we reduce the problem?
-Combustion of fuels containing hydrogen.
-It is a greenhouse gas.
-Try to burn less fossil fuels.
How is SO2 formed, what problems does it cause and how can we reduce the problem?
-Combustion of S containing compounds in fuels.
-Can cause acid rain.
-Remove sulphur from fuel before burning by flue gas desulphurisation.
How is nitrogen oxides (Nx) formed, what problems does it cause and how can we reduce the problem?
-Reaction of nitrogen with the oxygen in the air at very high temperatures.
-Can cause acid rain.
-Use catalytic converters in cars.
How is unburned hydrocarbons (methane) formed, what problems does it cause and how can we reduce the problem?
-Some fuel may not actually burn.
-Wates fuel and is a greenhouse has.
-Ensure engines are well-turned and there is a good supply of oxygen.
What is a catalytic converter?
-Have a ceramic honeycomb coated with a thin layer of catalytic platinum to give a large surface area, reduces the amount of catalyst needed and boots efficiency.
What do catalytic converters do?
-As combustion engines produce a range of harmful gases and the converters remove CO and NOx and unburned hydrocarbons at high temperatures turning them into CO2, N2 and H2O.
What is the equation for catalytic converters?
2CO + 2NO —–> 2CO2 + N2
How is acid rain caused?
-Sulfur impurities when burned can release SO2.
-SO2 and NO2 will dissolve in atmospheric water (clouds) and produce acid rain.
What are the equations for acid rain?
- H2O + NO2 —–> HNO3
- H2O + SO2 ——-> H2SO3
-SO2 + CaO ——> CaSO3
