Untit 16 - Acids, Bases, & Salts Flashcards
Litmus indicator
Red in acid
Purple in neutral
Blue in alkali
Methyl orange
Red in acid
Orange in neutral
Yellow in alkali
Phenolphthalein
Colourless in acid
Colourless in neutral
Pink in alkali
Strong acid
pH 0-2
Medium acids
pH 3-4
Weak acid
pH 5-6
Neutral
pH 7
Weak alkali
pH 8-9
Medium alkalis
pH 10-11
strong alkali
pH 12-14
Universal indicator in strong acid
Red
Universal indicator at pH neutral
Green
Universal indicator in strong alkali
Blue/black
Define an acid
An acid is a substance when, in aqueous solution, is a source of H+ ions
Define an alkali
An alkali is a soluble base, in aqueous solution they are a source of OH- ions
Solubility of all common sodium salts
Soluble
Solubility of all common potassium salts
Soluble
Solubility of all common ammonium salts
Soluble
Solubility of all nitrates
Soluble
Solubility of all common chlorides
Soluble
Except silver chloride which is insoluble
Solubility of all common sulfates
Soluble
Except barium and calcium sulfates are insoluble
Solubility of all common carbonates
Insoluble
Except sodium, potassium, and ammonium carbonate which are soluble
Preparation of soluble salts (3 methods)
Metal + acid –> salt + hydrogen
Base + acid –> salt + water
Carbonate + acid –> salt + water + carbon dioxide
What is a base
A base is a metal oxide or metal hydroxide
Preparation of insoluble salts
To prepare an insoluble salt two aqueous solutions are mixed together, one containing the cation and one containing the anion. The insoluble salt precipitates out. It is filtered off and the residue is washed with distilled water and dried on filter paper
