ACIDS, BASES AND SALTS
ACIDS-chemicals when dissolved in water will produce H⁺(aq) + anion]
BASES-chemicals (metal oxides and metal hydroxides), react with acids to produce a salt + water
ALKALIS-soluble bases (NaOH)
SALTS-ionic compounds produced when acid reacts with base (metal cation + anion from acid)

Acids
Litmus > red
Universal Indicator > yellow, orange/ red
reacts with metals H₂ + salt
reacts with bases salt + water
react with carbonates salt + CO₂ + water
Taste-sour
(vinegar-acetic acid, lemon-citric acid, soda water-carbonic acid,)

Bases
Litmus > blue
Universal Indicator > turns blue or violet
react with acids salt + water
react with ammonium salts salt + water + ammonia gas

AMMONIUM SALT + BASE > SALT + WATER + AMMONIA GAS
AMMONIUM SALT -(HEAT)-> ACID + AMMONIA GAS

Acids & Bases
Strong-most of the chemical ionises (from ions in water )Weak-a little of the chemical ionises
Dilute-c = < 1-2 mol/dm³
Concentrated-c = > 1-2 mol/dm³
Diprotic-gives 2 protons when dissolves in water (H⁺ considered a proton-electrons + neutrons lost)

Oxides
ACIDIC OXIDES-react with H₂O acid, oxides of non-metals
BASIC OXIDES-react with acid salt + water, oxides of metals
NEUTRAL OXIDES-don't react with H₂O or acid, oxides of a few non-metals ,H₂O,CO,NO (monoxides)
AMPHOTERIC OXIDES-react with acids & bases, oxides of a few metals, Al, Zn, Sn, Pb, Cr

Preparation and Purification of a Salt
Not soluble-use precipitation-add 2 salts
Soluble-use;METAL + ACID [not for (K, Na, Ca)-too reactive or (Cu, Ag, Au, Pt)-too unreactive]
ACID + BASE (do this with K, Na, Ca, Cu, Ag, Au, Pt)
ACID + CARBONATE (do this with K, Na, Ca, Cu, Ag, Au, Pt)
To purify, use methods of purification

pH
pH-the measure how acidic or alkaline a solution is. Comes from the conc. of H+ ions in the water
(pH 6.5=best soil, too acidic > limed, Ca(OH)₂)

Formula	NH3	CO2	Cl2	O2	H2	SO2
odour	X		X			X
colour			X
denser than air		X	X			X
less dense than air	X				X
similar density to air				X
almost insoluble in H2O				X	X

Cations-reaction = cation + OH^- cation hydroxide

Chemical Reactions + Electrolysis
Rate and Heat of Reactions + Reversible Reactions
The Periodic Table
Metals
Organic Chemistry
Non-metals
The Particulature Natrue of Matter
Experimental Techniques
Atoms, Elements and Compounds
Stoichiometry + Mole Concept

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