ATOMS, ELEMENTS AND COMPOUNDS
ATOM-made of sub-atomic particles, electrons, protons, neutrons

	Relative mass	Relative charge	Symbol
proton	1	+1	p+
electron	0 (1/1840)	-1	e-
neutron	1	0	n0

# of electrons = # of protons in an atomnucleus = protons + nucleons
proton(atomic)number-#of protons in an atomnucleon(mass)number-# of protons and neutrons in nucleus of an atom
isotopes-atoms with same proton number but different nucleon number
isomers-same atoms different structural config.

Isotopes -non-radioactive
 radioactive-give out harmful radiation which is harmful to life
  -produces energy (²³⁵U in nuclear reactors)
  -kill germs and cancer cells (⁶⁰Co-sterilize surgical instruments)

Electron Arrangement
All chemical reactions, chemical properties and most physical properties are due to electrons
Electrons arranged in shell around nucleus in an atom

Last/outer shell = valence shell (valence electrons=group #)
full valence shell = stable =noble gases
Atoms > gain/loses/share e^- > stable e- config. (gain/lose e^-s-make bonds-a strong force of attraction between +& -)

Ionic Substances
Ion =atom w/ a +/- charge (lose/gain electron) ion neutral
all metals-lose electrons (+ ion)non-metal-(many) gain electrons (-ion)
noble gases-remain single atoms, very stable
atoms form chemical bonds with each other to get stable electron config.

^e-H →[H]⁺ or H → H⁺, (e^- = valence electron), Hydrogen ion: H⁺

Acetate:	CH3COO-
Aluminium:	Al3+
Ammonium:	NH4+
Barium:	Ba2+
Bicarbonate:	HCO3-
Bisulphate:	HSO4-
Bromide:	Br-
Calcium:	Ca2+
Carbonate:	CO32-
Chloride:	Cl-
Copper II:	Cu2+
Fluoride:	F-
Hydrogen:	H+
Hydroxide:	OH-
Iodide:	I-
Iron III (ferric):	Fe3+
Lead:	Pb2+
Lithium:	Li+
Magnesium:	Mg2+
Nitrate:	NO3-
Oxide:	O2-
Phosphate:	PO43-
Potassium:	K+
Silver:	Ag+
Sodium:	Na+
Sulphate:	SO42-
Sulphide:	S2-
Zinc:	Zn2+
Dichromate:	Cr2O72-
Nitride:	N3-

Ionic Bonding (Metal+Non-metal)
Lattice-a giant structure of positive and negative ions held together by electrostatic attraction between the ions (continuous bonding)
In the reaction (electron transfer) between metal and non-metal electrons are lost and gained
Properties
Not volatile(high m.pt+b.pt.)-many strong bonds (a lot of energy to break)
Hard-many strong bonds
Brittle-ions of similar charge forced together > repel > break lattice
Soluble in water ;usually
Non-conductor of electricity as solids-charged particles are not mobile to carry electricity
Conductors of electricity as liquids + (aq) -has mobile charged particles to carry electricity

Magnesium oxide (MgO)-lining inside of furnaces- very high m.pt. + heat resistant-refractory

Covalent Molecules (Non-Metal+Non-Metal)
Substances compete for electrons, share electrons-covalent bond
A molecule-a group of atoms bonded to each other, have no bonds to other atoms, just weak forces of attraction
Covalent molecules: strong bonds in molecule, weak forces of attraction between molecules
Covalent bond represented by "-"
single bond-2 electrons shareddouble bond-4 electrons sharedtriple bond-6 electrons shared

Properties
Volatile(low m.pt.+b.pt.)- weak forces attraction between molecules
Soft-weak forces of attraction between molecules
Non-conductors of electricity*-no charged particles
*except if they react with water > form solutions containing ions [CO₂,HCl(gas),NH₃]

Macromolecules (Covalent networks) (non-metal+non-metal)
Exist as atoms joined by covalent bonds to other atoms. Bonding continuous for large number of atoms
Macromolecules-diamond, graphite, silicon dioxide, polymers
Properties
Low volatility- many strong bonds
Hard*-many strong bonds
Non-conductors of electricity**-no mobile/charged particles
*except graphite-soft: weak forces of attraction between layers
*except graphite-conductor: mobile delocalised electrons(not used for bonding, free and mobile to carry electricity)

Metals
They are metal ions that have delocalised ions. Ions attracted to delocalised ions-metallic bond
Properties
Low volatility*-many strong bonds
Hard-many strong bonds
Malleable(will go flat when hit)/ductile(ability to be made into wires)-flexible metallic bonds (electrons move + form new bond)
Conductors of electricity-mobile charged particles (delocalised electrons)
*Mercury-volatile-weaker metallic bonds (Group I metals-volatile)

Alloys
Mixture of a metal with another element, which changes the metal's properties (usually to make it more stable)
Steel-Fe + C-vehicles, ball bearings, medical instruments, tools, utensils
Brass-Cu + Zn-pins of electric plug, water pipes(plumbing)



Stoichiometry + Mole Concept
Acids + Bases
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

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