Aqueous Solutions (aq)
substance disolved in water
alkaline
acid
neutral
indicators
test for acidity / alkalinity
liquid
paper
different colours / different solutions
litmus
acid
red
neutral
purple
alkaline
blue
universal indicator
shows strength of acid / alkalis
more colours
pH scale
1 to 6
acid
7
neutral
8 to 14
alkaline
Phenolphthalein indicator
colourless in acid
pink in alkaline
Methyl Orange Indicator
pink in acid
yellow in alkaline
Acids
contain replaceable hydrogen atoms
chemcial reactions
metal atom replacement
salt compound formed
(see mind map on salts)
only in aqueous solution
form H+ ions
HCl (aq) ---> H+ (aq) + Cl- (aq)
basicity
number of H+ that can be replaced
hydrochloric acid : HCl
monobasic (one H+)
nitric acid : HNO3
monobasic (one H+)
sulphuric acid : H2SO4
dibasic (two H+)
phosphoric acid : H3PO4
tribasic (three H+)
Types
strong acid
produce all hydrogen ions available
HCl, HNO3, H2SO4, H3PO4
use one way arrow symbol --->
weak acid
partially dissociate
not release all hydrogen ions
molecules in equillibrium with ions
use double arrow symbol
ethanoic acid
vinegar
CH3COOH (aq) <--> CH3COO- (aq) + H+ (aq)
Bases / Alkalis
Base
hydroxides of metals
formed when oxide dissolves in water
alkali
oxides of metals
4Na (s) + O2 (g) ---> 2Na2O (s)
sodium + oxygen ---> sodium oxide
dissolve a base into water
alkali
Arrhenius : substances that dissolve in water to form hydroxide ions OH-
NaOH(aq) ---> Na+ (aq) + OH- (aq)
pH 8 - 14
strong alkalis
fully dissociate
release all hydroxide ions
sodium hydroxide
sodium oxide + water ---> sodium hydroxide
Na2O (s) + H2O (l) ---> 2NaOH (aq)
potassium hydroxide
KOH (aq) ---> K+ (aq) + OH- (aq)
use one way arrow symbol --->
weak base (weak alkali)
ammonia solution
ammonium hydroxide solution
NH4OH (aq)
NH3 (g) + H2) (l) <---> NH4+ (aq) + OH- (aq)
NH4OH(aq) <---> NH4+ (aq) + OH - (aq)
partial dissociation
‎Chemistry:
‎Acidity, Alkalinity,
‎Neutralisation
‎Aqueous Solutions (aq)
‎substance disolved in water
‎alkaline
‎acid
‎neutral
‎indicators
‎test for acidity / alkalinity
‎liquid
‎paper
‎different colours / different solutions
‎litmus
‎acid
‎red
‎neutral
‎purple
‎alkaline
‎blue
‎universal indicator
‎shows strength of acid / alkalis
‎more colours
‎pH scale
‎1 to 6
‎acid
‎7
‎neutral
‎8 to 14
‎alkaline

‎Phenolphthalein indicator
‎colourless in acid
‎pink in alkaline
‎Methyl Orange Indicator
‎pink in acid
‎yellow in alkaline
‎Acids
‎contain replaceable hydrogen atoms
‎chemcial reactions
‎metal atom replacement
‎salt compound formed
‎(see mind map on salts)
‎only in aqueous solution
‎form H+ ions
‎HCl (aq) ---> H+ (aq) + Cl- (aq)
‎basicity
‎number of H+ that can be replaced
‎hydrochloric acid : HCl
‎monobasic (one H+)
‎nitric acid : HNO3
‎monobasic (one H+)
‎sulphuric acid : H2SO4
‎dibasic (two H+)
‎phosphoric acid : H3PO4
‎tribasic (three H+)
‎Types
‎strong acid
‎produce all hydrogen ions available
‎HCl, HNO3, H2SO4, H3PO4
‎use one way arrow symbol --->
‎weak acid
‎partially dissociate
‎not release all hydrogen ions
‎molecules in equillibrium with ions
‎use double arrow symbol
‎ethanoic acid
‎vinegar
‎CH3COOH (aq) <--> CH3COO- (aq) + H+ (
‎aq)
‎Bases / Alkalis
‎Base
‎hydroxides of metals
‎formed when oxide dissolves in water
‎alkali
‎oxides of metals
‎4Na (s) + O2 (g) ---> 2Na2O (s)
‎sodium + oxygen ---> sodium oxide
‎dissolve a base into water
‎alkali
‎Arrhenius : substances that dissolve
‎in water to form hydroxide ions OH-
‎NaOH(aq) ---> Na+ (aq) + OH- (aq)
‎pH 8 - 14
‎strong alkalis
‎fully dissociate
‎release all hydroxide ions
‎sodium hydroxide
‎sodium oxide + water ---> sodium
‎hydroxide
‎Na2O (s) + H2O (l) ---> 2NaOH (aq)
‎potassium hydroxide
‎KOH (aq) ---> K+ (aq) + OH- (aq)
‎use one way arrow symbol --->
‎weak base (weak alkali)
‎ammonia solution
‎ammonium hydroxide solution
‎NH4OH (aq)
‎NH3 (g) + H2) (l) <---> NH4+ (aq) + OH- (
‎aq)
‎NH4OH(aq) <---> NH4+ (aq) + OH - (aq)
‎partial dissociation
Note
Gallery
Chemistry: Acidity, Alkalinity, Neutralisation
Gallery
Sheet 1
100%
500 %
400 %
300 %
200 %
150 %
120 %
100 %
80 %
50 %
20 %
Embed Code
Facebook
Twitter
LinkedIn
Upload by
ScienceMindMaps
on Jul 30, 2014
Download
214.8kb
Open With App
Edit