Alkanes

Combustion of Alkanes

Reference to the Specification

Alkanes

The general formula for an alkane is CnH2n+2All possible bonds are used Saturated hydrocarbons are compounds which contain only carbon and hydrogen bonded exclusively with single bonds.Combustion of Alkanes Burning alkanes in plenty of oxygen allows for complete combustion

alkane + oxygen carbon dioxide + waterComplete CombustionCombustion EquationE.G: CH4(g) + 2O2(g) CO2(g) + 2H2O(g)

Carbon Dioxide is a Greenhouse gas. This contributes to Global WarmingIncomplete Combustion Burning alkanes in a limited supply of oxygen leads to incomplete combustion

alkane + oxygen carbon monoxide + water

Incomplete combustion EquationE.G: CH4(g) +3/4 O2(g) CO(g) +2H2O(g)Carbon Monoxide is a Poisonous gas. Depending on the alkane burnt ,carbon (s) can also be produced. Carbon (soot) contributes to global dimming+NOx & Unburned HydrocarbonsNOx =General formula for Nitrogen oxidesToxic & Poisonous High temperatures and pressures in a car engine cause nitrogen and oxygen in the air to reactE.G: N2g) +O2(g) 2NO(g) Nitrogen oxide can further react to produce nitrogen dioxide: 2NO(g) +O2(g) 2NO2(g)

pollution from burning fuelsLeads to ACID RAINUnburned HydrocarbonsEngines dont burn all of the fuel molecules

Unburnt Hydrocarbons

irritates peoples eyes aggravates respiration problemslung problemsSmogCatalytic ConvertersRemoves pollutants from the exhaust gases by converting more than 90% of the pollutants into less harmful gases.

E.G: 2NO (g) N2 (g) + O2 (g) CO (g) + 1/2O2 CO2 (g) C9H20 (g) + 14O2 9CO2 + 10H2O (g) Catalytic Convertors Large Surface AreasTransition metals

Flue gases are waste gases from boilers and furnacesThese have to be removed because they can cause acid rain

O2CO2H2O

Carbon DioxideMethaneWater VapourThe burning of fossil fuels adds additional man-made carbon dioxide to the cycleThank You for Listening