2(g) Acids, bases and salt preparations Flashcards
Nitrates
All nitrates are soluble
Chlorides
Common chlorides are soluble, except those of silver and lead(II)
Sulfates
Common sulfates are soluble, except for those of barium, calcium and lead(II)
Carbonates
Common carbonates are insoluble, except for those of sodium, potassium and ammonium
Hydroxides
common hydroxides are insoluble except for those of sodium, potassium and calcium (calcium hydroxide is slightly soluble).
Common sodium, potassium and ammonium compounds
Soluble
Acids (in terms of proton transfer)
Proton Donor
Alkalis (in terms of proton transfer)
Proton Acceptor
Salt equations: MASH
Metal + Acid -> Salt + Hydrogen
Salt equations: BAWS
Base + Acid -> Water + Salt
Salt equations: AAWS
Acid + Alkali -> Water + Salt
Salt equations: CAWCS
Metal carbonate + Acid -> Water + Carbon Dioxide + Salt
2.39 describe an experiment to prepare a pure, dry sample of a soluble salt, starting from an insoluble reactant
- Add metal/metal oxide/metal carbonate in excess to the acid (to react all the acid)
- Remove excess through filtration
- Heat filtrate (in evaporating basin + bunsen burner) to reduce by half/until saturated
- Remove heat
- Leave in a warm place to dry
2.40C describe an experiment to prepare a pure, dry sample of a soluble salt, starting from an acid and alkali
- Add reactants to beaker and mix
- Filter
- Heat filtrate (in evaporating basin + bunsen burner) to reduce by half/until saturated
- Remove heat
- Leave in a warm place to dry
2.41C describe an experiment to prepare a pure, dry sample of an insoluble salt, starting from two soluble reactants
- Add reactants to beaker and mix
- Filter
- Rinse with distilled water (to remove impurities)
- Leave in a warm place to dry
2.42 practical: prepare a sample of pure, dry hydrated copper(II) sulfate crystals starting from copper(II) oxide
- Add copper oxide in excess to sulfuric acid and stir with glass rod
- Warm with bunsen burner
- Solution turns blue as reaction occurs
- To remove excess copper oxide, filter
- Heat filtrate and reduce by half
- Leave in a warm place to dry
2.43C practical: prepare a sample of pure, dry lead(II) sulfate
- Add lead nitrate to sodium sulfate solution
- White precipitate of lead sulfate is formed
- Filter
- Rinse with distilled water.
- Leave in a warm place to dry
Alkalis
Bases that are soluble in water
What substances can act as bases?
metal oxides, metal hydroxides, ammonia, metal carbonates