Heat/temperature videos: Heat | Temperature | Minute Physics
Water treatment in SA:
Drinking water: 1 | 2
Sewage treatment: 1 | 2
Desalination
Know the previously required ions and acids.
Memorise that nitrates, sodium, potassium and ammonium are always soluble.
Use the solubility rules to predict whether or not a given ionic compound will be soluble.
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chlorides, iodides and bromides (soluble except silver, mercury and lead)
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fluorides (soluble except group 2 metals, manganese and lead)
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oxides (insoluble except calcium and barium)
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sulfates (soluble except barium, strontium and lead)
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carbonates and phosphates (insoluble)
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hydroxides (insoluble except lithium)
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sulfides (insoluble except group 2 metals)
Use the solubility rules to deduce the cation in an ionic compound, given data on what it forms a precipitate with.
Determine whether a given reaction with water is dissociation or ionisation.
Memorise the following reaction types and be able to write balanced ionic (i.e. take out spectator ions) equations for them.
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Acid + Base → Salt + Water
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Acid + Carbonate → Salt + Water + CO2
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Acid + reactive metals → Hydrogen gas + salt
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Reactive metals + water → Hydrogen gas + metal hydroxide
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Metal + non-metal → Salt
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Precipitation reactions – use the solubility rules
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Single displacement reactions – use the reactivity series
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Burning in air – combine with oxygen
Solve problems using the equations E = mcΔT and E = mL
Answer questions requiring understanding of the following:
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particle theory of matter
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latent heat of fusion
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latent heat of vaporisation
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specific heat capacity
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soaps and detergents
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hardness of water (and the ions involved)
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properties of water (polarity, hydrogen bonding, relatively high specific heat capacity)
Describe the water treatment process, and explain how a flocculant (aluminium sulphate) works