12.4 Combustion of alkanes

Combustion reactions give out [A] and have [B] negative enthalpies of combustion ?

[A]
[B]

A = heat
B = Large

What does complete combustion produce ?

carbon dioxide and water

What does incomplete combustion produce ?

carbon monoxide

How are nitrogen oxides formed?

Nitrogen and oxygen from the air react in the high temperature of an engine

Why are nitrogen oxides bad?

NOx gases react to form smog and acid rain as well as being central to the formation of fine particles and ground level ozone, both of which are associated with adverse health effects.

Why is sulfur dioxide released?

Sulfur impurities during burning from crude oil

Why is sulphur dioxide bad?

Acid rain

Why are carbon particulates bad ?

exacerbate asthma and cause cancer ?

Why is excess carbon dioxide bad in the atmosphere

cause of the increase in the earths temperature

True or false : water is a greenhouse gas

True water is a greenhouse gas

What is flue gas desulfurisation?

the process of removing sulfur dioxide from flue gas

Why are catalytic converters used?

To remove impurity's from petrol when burnt

What is a catalytic converter?

Cars can have catalytic converters, which will change harmful compounds into less harmful ones . Catalyst made of platinum and rhodium .Honey comb structure = large surface area .

What is the greenhouse effect?

The process by which gases hold heat in the atmosphere

Combustion of methane

CH4 + 2 O2 → CO2 + 2 H2O

Combustion of ethane

2C2H6+7O2→4CO2+6H2O

Incomplete combustion of propane

2 C3H8 + 9 O2 → 4 CO2 + 2 CO + 8 H2O

Acid rain equations

2SO2 + O2 -> 2SO3
Sulphur dioxide + oxygen = sulphur trioxide

S03 + H20 -> H2SO4
Sulphur trioxide + water = sulphuric acid

Reaction in catalytic converter simplified

Hydrocarbons + nitrogen oxides ---> nitrogen + carbon dioxide + water