Atomic Structure

Smallest particles of matter

Proton Mass:1 Charge +1

Neutron Mass:1 Charge 0

Electron Mass:~0 Charge -1

Protons and neutrons collectively = nucleus

Number of electrons = number of protons

Energy Levels: 2,8,8,18,18

Electrons are far away from the nucleus

Atom: Smallest stable particle

Element: 1 Type of atom

Compound: More than 1 element

Molecule: 2 or more atoms chemically bonded

Name of metal comes first e.g: Sodium Carbonate - NaCO3

2 elements ends in -ide e.g:Magnesium Bromide - MgBr2

3 elements & one is oxygen, ends in -ate Copper Sulphate - CuSO4

2 or more of same element nothing e.g: H2

Neutrons = Mass number - Atomic Number

In an Atom, Protons = Electrons

Group = electrons in outer shell

Period = number of energy levels

Numerical name = symbol, electron configuration e.g. Sodium = Na 2, 8, 1

Reactant + Reactant => Product

Chromium Sulphate + Sodium Hydroxide => Chromium Hydroxide + Sodium Sulphate

Cr2(SO4)3 + NaOH => Cr(OH)3 + Na2SO4

Cr2(SO4)3 + 6NaOH => 2Cr(OH)3 + 3Na2SO4

When atoms dont have full shells they are not stable

Only number of electrons change

Cation - ion with positive charge [Ion]+ 

Anion - ion with negative charge [ion]-

Li => [Li}+ + 1e-

[O]2- => O + 2e-

Different number of Neutrons

12                                    14

     C     = carbon atom          C  = carbon isotope (Carbon-14)

6                                       6 

A method of seperating and analysing a mixture of soluble chemical substances

Rf = Compund travel distance / Solvent front

Rf compares components of various samples

Filtration: Seperating an insoluble solid from a liquid

Crystalisation: Evaporation

Evaporation and condensation

Simple distillation: No liebig condeser, takes longer, has an atmospheric coolant, lose water through steam

Fractional: Lose on water, less time, cold water coolant (through liebig condenser)

Occurs between cation and anion

Metals form cations

Non-metals form anions

Opposites attract and form an ionic bond

Na + Cl => NaCl

NaCl is neutrally charged

Sodium loses an electron

Chlorine gains one

Occurs between two non-metals

Not as strong as ionic bonds

Sharing electrons