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Chem Review - Coggle Diagram
Chem Review
Periodic Trends
Atomic Radius
INCREASE
down
DECREASE
up
Ionisation Energy
First & Successive
the first ionisation requires
less energy
than successive ionisation energies
Electronegativity
nuclear charge
n. protons - n. inner/shielding electrons
Spectroscopy
Mass Spectroscopy
used to work out presence of isotopes
mass spectrometer
VIAD (sexy vampire)
Vaporisation of the sample
Ionisation of sample (energy from the heat)
AAS
used to work out concentrations of solutions
and also for working out percentage composition
atoms will absorb every wavelength of light except that of which they produce
ground state & exited state
each element has unique emission/absorption spectra, as the energy required to jump back to the ground state differs for each element
photons emitted have a unique wavelength for each element
Emission Spectroscopy
When exiting the excited state, electrons emit energy as a photon of light
flame tests - substances are heated in a bunsen burner flame and colour changes are observed
Isotopes
Same chemical properties but different physical properties
physical
melting point
boiling point
mass
density
viscosity
conductivity (heat & electricity)
particle size
chemical
reaction with oxygen
reaction with acids/bases
reactivity
Calculations
Relative Atomic Mass
weighted average of an element (taking into account relative abundances of isotopes)
Hydrated Formulas
when a molecule is surrounded by H2O
Percentage Composition
percentage abundance of elements in a compound/molecule
Relative Molecular / Formula Mass