Atomic Structure and The Perodic Table Flashcards
Sub atomic particles Mass and Charge
Proton - mass 1 - charge +1
Electron- mass 0 - charge -1
Neutron - mass 1 - charge 0
Atomic Number
Number of protons in the nucleus of an atom
Mass number
Total number of protons and neutrons in the nucleus of an atom
Isotopes
Atoms of the same element that have the same number of protons but a different number of neutrons
Relative atomic mass
Average mass of the atoms of an element relative to 1/12 of the mass of a carbon-12 atom
Relative Isotopic mass
The mass of one isotope relative to 1/12 of the mass of a carbon-12 atom
Mass spectrometry Step 1:
Ionisation : atoms ionised in a gaseous state to produce positive ions using high energy electrons
Mass spectrometry step 2:
Acceleration: Ions are accelerated so the all have to same kinetic energy
Mass spectrometry step 3:
Deflection: Ions deflected by a magnetic field according to their masses
Mass spectrometry step 4:
Detection: Beam of ion pass through a detector
Mass spectrometry stick diagram
Shows the strength of the signal produced by ions of varying mass-to-charge ratio. Y-axis = Relative abundance , X-axis = m/z value
Relative atomic mass formula
(Ar of each isotope x % of each isotope) / 100
Information of Fragmentation patterns
-Isotopic composition
-Relative atomic mass
-Relative molecular mass
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Electrons in atoms
-SPDF notation
-Electrons spin in opposite directions to counteract electric repulsion
First Ionisation Energy
The amount of energy required to remove 1 mole of electrons from 1 mole of gaseous atoms to produce 1 mole of gaseous +1 ions
what is the general trend of first ionisation energy across a row?
First ionisation energy usually increases across a row as nuclear charge increases while electron shielding stays constant
how does the ionisation of paired electrons compare to unpaired electrons ?
Paired electrons have a lower ionisation energy compared to unpaired due to electric repulsion
what is the trend of first ionisation energies down a group?
Decrease down a group as valance electron(s) increase in distance from the nucleus (additional nuclear charge nullified by electron shielding)
what does a jump in successive ionisation energies indicate?
New energy levels
Periodicity
Repeating trends in physical and chemical properties
