TAE: Acidic Oxides and the Atmosphere Flashcards
What are oxides?
Oxides are a class of compound that often display acidic or basic properties under certain conditions. Whether an oxide is acidic or basic depends on whether they are metal, non-metal or semi-metal.
What are the trends in regards to the position of metal/non metal oxides o the periodic table?
- Basicity increase
down a group - Acidity increases up a group
- noble gases do not form oxides
What are acidic oxides and examples?
Examples: CO2, SO2, NO2, P2O5)
Acidic oxides are generally oxides of non-metals.
They are all covalent compounds and occur towards the right and top of the Periodic table.
- Reacts with water to form acids
- Reacts with bases to form salts
What are basic oxides and examples?
Examples: (CUO, FE2O3)
Oxides of metals
Ionic compounds that occur at LEFT of periodic table
What are amphoteric oxides and examples?
Examples: (ZNO, PB0, AL2O3, AL(OH)3)
Amphoteric oxides react with both strong acids and strong bases (i.e. display both acidic and basic properties).
They are located on the borderline between metals and non-metals.
What are neutral oxides and examples?
Examples: CO, NO N2O
Do not react with either acids or bases
What are the charecteristics of a system at equilibrium?
– Macroscopic properties will stay constant
– Concentrations of reactants and products stay constant but not necessarily equal.
– Continual microscopic change occurs between reactants and products.
– The rate of forward reaction is equal to rate of backward reaction (equilibrium is dynamic).
– A catalyst will increase the rate of a reversible reaction in both directions. It will make a
system reach equilibrium faster, but will not change the concentration of substances at equilibrium or the equilibrium position.
How does concentration affect equilibrium?
If a reactant or product is added to a mixture at equilibrium,
then the equilibrium moves in the direction which consumes some of the added substances.
How does pressure affect equilibrium?
ONLY AFFECTS GASES
If you increase pressure, equilibrium shifts to less gaseous mole
Identify natural and industrial sources of sulfur dioxide
Natural: volcanic gases, bushfires, geothermal hot springs.
Industrial: combustion of fossil fuels, smelting of metal sulphides, power stations.
Identify natural and industrial sources of nitric oxide and nitrogen dioxide - (NO2)
Natural: the reaction of atmospheric nitrogen and oxygen due to high temperatures of
lightning produces nitric oxide, which then slowly reacts with oxygen to form nitrogen dioxide.
Industrial: combustion of fossil fuels in cars and power stations.
Identify natural and industrial sources of nitric oxide and nitrous oxide - (N2O)
Natural: formed by the action of bacteria on nitrogenous material in soils; use of nitrogenous
fertiliser increases raw material for the bacteria, increasing levels of nitrous oxide.
Industrial: fuel for racing cars, sedative/analgesic.
How is health threatned by the relese of SO2 and NO2
Both sulfur dioxide and nitrogen dioxide are respiratory irritants
as they cause breathing difficulties, especially for asthmatics. At higher concentrations,
causes extensive tissue damage as it forms nitric acid, .
How does NO2 contribute to pollution
it causes photochemical smog in
the form of ozone, an air pollutant which affects visibility due to small particles in the air.
Explain the formation of acid rain
Acid rain is any rain that has a pH of less than 5
Rain water can become quite acidic due to the HIGH SOLUBILITY of acidic oxide gases.
