Dalton's atomic structure (1808)
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All matter consists of atoms
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Elements consist of atoms
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Compound consist of atoms of more than one element
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In a reaction atoms are not created nor destroyed
Thomson's model (1906)
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"Plum pudding" model
Rutherford's gold foil experiment
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Proved the empty space in an atom
Sub atomic particles
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Proton
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Neutron
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Electron
Nuclear symbol
A: number of protons + neutrons
Z: number of protons
Mass spectrometer
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Used to determine the Relative atomic mass of an element
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5 Stages: Vaporization-->ionization--> acceleration-->deflection-->detection
Tip: You only need to know the order of the stages, not how each stage works.
Radio isotopes
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medical chemistry
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Iodine 131 to obtain image of tyreoid gland
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iodine 125 to treat cancer and tumors
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Cobalt 60 in radiotherapy
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Dating
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Carbon 14 in cosmic, geological and archeological dating
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Half-Life: time it takes for an amount of radioactive isotopes to decrease to one half of its initial value
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Example: carbon half-life: 5730 years
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Emission Spectra
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A pure gaseous element subjected to a high voltage and reduced pressure will emit a certain wave length.
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Quantisation energy:
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formula:
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When the electron falls back from the excited state to the ground state it emits a photon, a discrete amount of energy.
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Hydrogen line emission spectrum
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Series
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At the limit of convergence of the spectra there is a continuum. Beyond this energy there is a free electron.
Orbitals (Quantum mechanical model)
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Region in space where there is a high probability of finding an electron
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each orbital can hold a maximum of 2 electrons
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s orbital is spherically symmetrical
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p orbital is dumbbell shaped. There are 3 atomic orbitals, each in one cartesian axes

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Orbital diagram:
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Example: Zn
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Condensed configuration:
- Example:
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Configurations
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Full electron configuration:
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Example:
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