Amphoteric oxides
________: those that react with both an acid and an alkali to give a salt and water.
Solution
________ is heated in an evaporating dish to form soluble salt crystals.
Substances
________ that change colour when added to an acid /alkali are called indicators.
Phenolphthalein
________ is added to an alkali (soluble base)
oxides
Are the ________ and hydroxides of metals.
Excess insoluble compound
________ (metal /base /carbonate) reacts with acid whilst being heated.
soluble salt
Heat in evaporating dish to form ________ crystals.
Acid
Proton Donors/ Dissociate into H+ ions
Alkalis
(are bases that dissolve in water)
· Give solutions that contain OH
ions
The scale
pH scale
It runs from 1
14
Acidic oxides
Non-metal oxides that dissolve in water and form an acidic solution
Basic oxides
Metal oxides that dissolve in water and form basic solution
Neutral oxides
Oxides with a pH of 7
Amphoteric oxides
those that react with both an acid and an alkali to give a salt and water
Method A
Neutralization
Method B
Titration
Method C
Precipitation
Note
one soluble salt should always be a potassium or sodium solution (eg
Acid + Alkali
Acid + Alkali -> Salt + Water
Acid + Metal
Acid + Metal -> Salt + Hydrogen
Acid + metal carbonate
Acid + metal carbonate -> salt + carbon dioxide + water
Alkali + ammonium salt
Alkali + ammonium salt-> salt + ammonia + water
Result for Aluminum ions in NaOH
White soluble precipitate, turns colorless in excess
White precipitate, insoluble in excess