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Combustion____________________________________________________________

Hydrocarbon Combustion Hydrocarbons are molecular (covalent)

compounds made ____________________ ____________________

Many are used as fuels; _______________ ________________________________

Combustion reactions produce heat (_______________ ) & light (_______________ _______________ )

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Complete or Incomplete?4

All hydrocarbons ______, provided they are ______enough and have sufficient ______

Depending on the products that form, we classify combustion as either __________or __________

Complete Combustion

Complete Combustion occurs when O2 is

__________

It releases the ____energy and the

__________ flames General Equation:

CXHY + O2(g) CO2(g) + H2O(g) + energy

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Incomplete Combustion

Incomplete Combustion occurs when O2 is in

__________ __________ It releases _____energy and results in

__________, sooty, yellow, cooler flames

Products (in addition to CO2 and H2O)

CO(g) (__________)

C(s) (soot, ash, _____of solid carbon products)

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Problems of Incomplete Combustion

1) __________; releases only a portion of the energy contained in the fuel

city/highway/idle

2) __________; many chemicals in soot are toxic when inhaled, also builds up around engine

3) __________;- mistaken for O2 by hemoglobin in blood

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Combustion Concerns CO2 and H2O are greenhouse gases;

contributing to _________ _________ Many fuels contain __________ such

as sulfur and heavy metals that contribute to air pollution

Firefighters

Forest Fires

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This diagram shows how the polluting effects of nitrogen combustion in vehicle engines can be largely eliminated by catalytic conversion. Match each chemical equation to the correct position in the diagram.

Combustion in the engine

Catalytic conversion Without catalytic conversion

Further reaction in the atmosphere

Formation of acids in the atmosphere

Catalytic Converter