Question

What are the issues, if any, due to burning compounds with high resultant quantities of CO2 or burning compounds with low resultant quantities of CO2? How do you determine from the results of CO2 and H2O from your balanced combustion equations, if they indicate any potential environmental issues or concerns for people that may work in such conditions? Qualify your responses.

Answer 1

a) Combustion is a process in which a compound i.e the hydrocarbon reacts with oxygen in the air to produce CO2 and H2O. Burning compounds with high resultant quantities of CO2 contributes towards global warming while low resultant qantities of CO2 suggests incomplete combustion and therefore higher CO gas which can be potentially explosive.

b) 'Perfect combustion' condition is when oxygen combines with a fuel in stoichiometric proportion giving optimized levels of CO2 and H2O. For example, consider the combustion of methane

Air is 79% N2 and 21% O2 i.e the mole ratio for O2 : N2 = 1: 3.76 whic gives 29 g/mol as the molecular weight of air

CH4 + 2 (O2 + 3.76 N2) ---- CO2 + H2O + N2

here 1 mole of CH4 (Fuel) combines with 2 moles of O2 (Air) for complete combustion. therefore, the amount of air required which is the ideal Air-Fuel ratio would be:

AFR = mass of air/mass of fuel

= (2 *4.76moles of air * 29 g/mole)/ 1mole of CH4 * 16 g/mol = 17.3 g of air/g of CH4 fuel