What is a base? A base is the oxide or hydroxide of a metal
What is an alkali? An alkali is a soluble base
- All alkalis are bases, but not all bases are alkalis
PROPERTIES OF SODIUM AND POTASSIUM HYDROXIDE
action of air on the solids:
What is deliquescence? White pellets dissolve to become a solution.
- The process of a substance absorbing moisture from the air until
it has dissolved in the absorbed water and formed a solution is
called deliquescence.
preparation of solution:
What happens when you
White pellets dissolve in water and the beaker warms up.
dissolve them in water? - Both solids are very soluble and the process of dissolving them is
exothermic.
Are sodium and potassium action on indicators:
hydroxide acidic or alkaline Litmus solution stays purple, Methyl goes orange to yellow,
Phenolphthalein goes colourless to magenta
and how do you know?
- They are alkaline
action on acids:
Initially no change in the colour of solution as the indicator remains red,
but as more is added, the indicator goes through the colours of universal
indicator quickly and remains blue at the end
- They will neutralise acids
action on solution of salts:
What type of substance forms Copper sulphate -> blue precipitate forms (copper hydroxide)
coloured precipitates? Iron(III)chloride -> brown precipitate forms (iron(III)hydroxide)
Magnesium sulphate -> white precipitate forms (magnesium hydroxide)
- Transition metals form coloured precipitates
What is precipitation? Precipitation occurs when two soluble substances combine to become a
solid or a precipitate.
preparation
Ammonia is prepared by heating a mixture of an ammonium salt with an
How do you prepare ammonia?
alkali. Ammonium chloride and dry calcium hydroxide (slaked lime) are
usually used.
What is the equation for this ammonium chloride + calcium hydroxide → calcium chloride + water + ammonia
reaction? 2NH4Cl + Ca(OH)2 → CaCl2 + 2H2O + 2NH3
The ammonia is dried by passage through calcium oxide (quicklime) in a
How is the ammonia collected
and why? drying tower and collected by upward delivery.
What is an alkali? An alkali is a soluble base
- All alkalis are bases, but not all bases are alkalis
PROPERTIES OF SODIUM AND POTASSIUM HYDROXIDE
action of air on the solids:
What is deliquescence? White pellets dissolve to become a solution.
- The process of a substance absorbing moisture from the air until
it has dissolved in the absorbed water and formed a solution is
called deliquescence.
preparation of solution:
What happens when you
White pellets dissolve in water and the beaker warms up.
dissolve them in water? - Both solids are very soluble and the process of dissolving them is
exothermic.
Are sodium and potassium action on indicators:
hydroxide acidic or alkaline Litmus solution stays purple, Methyl goes orange to yellow,
Phenolphthalein goes colourless to magenta
and how do you know?
- They are alkaline
action on acids:
Initially no change in the colour of solution as the indicator remains red,
but as more is added, the indicator goes through the colours of universal
indicator quickly and remains blue at the end
- They will neutralise acids
action on solution of salts:
What type of substance forms Copper sulphate -> blue precipitate forms (copper hydroxide)
coloured precipitates? Iron(III)chloride -> brown precipitate forms (iron(III)hydroxide)
Magnesium sulphate -> white precipitate forms (magnesium hydroxide)
- Transition metals form coloured precipitates
What is precipitation? Precipitation occurs when two soluble substances combine to become a
solid or a precipitate.
preparation
Ammonia is prepared by heating a mixture of an ammonium salt with an
How do you prepare ammonia?
alkali. Ammonium chloride and dry calcium hydroxide (slaked lime) are
usually used.
What is the equation for this ammonium chloride + calcium hydroxide → calcium chloride + water + ammonia
reaction? 2NH4Cl + Ca(OH)2 → CaCl2 + 2H2O + 2NH3
The ammonia is dried by passage through calcium oxide (quicklime) in a
How is the ammonia collected
and why? drying tower and collected by upward delivery.
