2. Why are pollutant gases that absorb in the \"window\" region of thermal IR of
ID: 1032189 • Letter: 2
Question
2. Why are pollutant gases that absorb in the "window" region of thermal IR of more concern than gases that absorb wavelengths that overlap with carbon dioxide and water? a) Write the balanced chemical equation for the complete combustion of methane in oxygen to form carbon dioxide and water. b) Data taken over time reveal an increase in CO2 irn the atmosphere. The large increase in the combustion of hydrocarbons since the Industrial Revolution is often cited as a reason for the increasing levels of CO2. However, an increase in water vapor has not been observed during the same period. Given that the general equation in part (a) can be applied (and rebalanced) for the combustion of any hydrocarbon, does the difference in these two trends disprove any connection between human activities and global warming? Explain your reasoningExplanation / Answer
2. The wavelength of photons associated with the window region of thermal IR is relatively higher than that absorbed by carbon dioxide or water. This implies that those gases tend to absorb less dangerous thermal IR and tend to reflect a much greater spectrum of thermal IR compared to carbon dioxide and water which absorb some overlapping regions of thermal IR thus being relatively less effective as a greenhouse gas than the ones in scrutiny making the latter capable of heating up the earth's surface much faster.
3.a) CH4 + 2O2 -----> CO2 + 2H2O
b) Complete combustion of pure hydrocarbons always release both carbon dioxide and water as they are composed of carbon and hydrogen which are oxidised to carbon dioxide and water. Thus if burning of hydrocarbons is the sole source of carbon dioxide levels in the atmosphere, there should be an equivalent quantity of water vapour level increase too. In general, the complete combustion of a hydrocarbon can be represented as CmHn + (m + n/2)O2 -----> mCO2 + (n/2)H2O
Related Questions
drjack9650@gmail.com
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.