This self study guide includes followings
Acid , base and salt
Oxides
Preparation of salts
Identification of cation, anion and gases.
Covers core and extended syllabus contents.
Compiled by M.S.Liyanage (BSc, MSc)
,Syllabus content
Acids, bases and salts
,( Extended students should study core and supplement both)
, Acid , base and salts
Any chemical substance you choose from your lab, it may be an acid, base or a
neutral substance ( salt).
Acids
Acids only show their properties when they are in aqueous solution. This is
because, in water, acids form the hydrogen ions (which are also called
PROTONS). These ions are responsible for acid properties
A n acid is an H+ ion (or proton) donor
A base is an H+ ion (or proton) acceptor or OH- donor .
If an acid to behave as an H+ ion donor , there must be an another substance
present to accept the H+ ion. So the water, in the aqueous acid solution, is base
and accepting an H+ ion.
Generally:
HA(aq) + H2O(l) → H3O+(aq) + A− (aq)
acid base hydrozonium ion
Hydrozonium ion is unstable and splits to H+ and H2O
When a substance dissolves in water, it forms an aqueous solution shown
by the symbol (aq).
For example, with
hydrochloric acid in water: HCl(aq) + H2O(l) H3O+ (aq) + Cl-(aq)
H3O+(aq) H+ (aq) + H2O (l)
Some common acids
The main acids you will meet in chemistry are:
Hydrochloric acid HCl (aq)
Sulfuric acid H2SO4 (aq)
Nitric acid HNO3 (aq)
Ethanoic acid CH3COOH (aq)
Hydrogen carbonate acid H2CO3