Atomic Structure - created from Mind Map

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PEN

Proton

Electron

Neutron

Mass number = proton + neutrons

In atom P=E

Isotope

Charge = +1

Relative mass = 1

Charge = -1

Relative mass = 0

No charge

Relative mass = 1

Different number of neutrons

Chemical properties depend on electrons

same proton number

Electrons arranged same in isotope so same chemical properties

Physicals properties differ slightly because mass changes

Mass Spectrometer

VIADD

m/z on x axis Abundance (usually %) on y

Vapourisation

Ionisation

Acceleration

Deflection

Detection

Electron gun fires high energy electrons

He(g) --> He+ (g) + e-

But use minimum as want least 2+ ions

Some 2+ ions created Mg+(g) + e- --> Mg2+ (g) +2e-

Negative plates attract +ions which accelerates

Electromagnet produces variable magnetic field

Amount deflected depends on m/z

mass/charge

Larger m/z the smaller the deflection

24Na+ and 48Ti2+

Same m/z ratio 48/2 and 24/1 = 24

So deflected by same amount

Tiny current is produced as ion takes electron from negative plante

This is then amplified and sent to computer

More currents = higher peak

current depends on number of ions

From graph can calculate relative atomic mass (Ar)

Ar=((% x m/z) + (% x m/z) +.....)/total %

Ar = average mass of one atom of an element / 1/12 the mass of one carbon-12 atom

Mr = average mass of one molecule/ 1/12 the mass of one carbon-12 atom

Electronic configuration

Orbitals

Ionisation Energies

1s 2s 2p 3s 3p

Examples

4s filled befoe 3d

electrons are paired with opposite spin

with p and greater orbitals electrons remain unpaired filling empty orbitals first but with parallel spin

Na 1s2 2s2 2p6 3s1

Ti 1s2 2s2 2p6 3s2 3p6 3d2 4s2

Exceptions

Cr 1s2 2s2 2p6 3s2 3p6 3d5 4s1

Cu 1s2 2s2 2p6 3s2 3p6 3d10 4s1

Increases Across period 3

Decreases down Group 2

Second ionisation energy always higher

Proton number increase

Shielding stays the same

Atoms become smaller as you go across

Exceptions (Decreases)

Aluminium - further from nucleus as it is first element with 3p electron

Sulfur - first paired 3p electron so decrease due to electron-electron repulsion

More shielding as you go down (offsets proton increases)

Further from nucleus

less shielding

lost from ion

Ion is smaller

Atomic Structure