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Chaptes 2 - Atoms, Ions and Compounds - Coggle Diagram
Chaptes 2 - Atoms, Ions and Compounds
Atomic structure
Nuclear atoms
Conists of a nucleus, made up of protons and neutrons
Electrons occupies a region outside the nucleus, they're arranged in shells
Properties
Mass
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A proton and neutron virtually have the same mass, so they have a relative mass of 1
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A neutron has a slightly greater mass, but this is ignored
Charge
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Charge of a proton and electron are equal and opposite, so the charges balance
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The actual charged of subatomicparticles is tiny, so relative chargers are used
Building the atom
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The larger an atom is, the more neutrons are needed
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Isotopes
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Number of neutrons can be different, usually with a narrow range
Isotopes are atoms of the same element with the same number of protons an electrons, but a different number of neutrons, and different masses
Chemical reactions
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There may be sml differences in physical properties, higher mass isotopes having higher melting points and density
Ions
A charged atoms, number of electrons doesn't equal number of protons
Cations - positive ions, atoms with fewer electrons that protons
Anions, negative ions, atoms with more electrons that protons
Formed when an atom loses or gains electrons, no longer netural
Relative mass
Carbon -12
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Standard mass for atomic mass = 1u, or1/12th the mass of a carbon-12 atom
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Why is it used?
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Solid, so easier to handle
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Relative atomic mass
The weighted mean mass of an atom of an element compared with 1/12th the mass of an atom oc carbon-12
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Determining Ar
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Process
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4) Ions are accelerated, heavier ions move more slowly than lighter ions, and are also more difficult to deflect, this causes ions of each isotope to seperate
5) Ions are detected on a mass spectrum as a mass-to-charge ratio. Each ion being detected adds to the signal, greater the abundance, the larger the signal
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For an isotope with a +1 charge, the ratio equals the relative isotomic mass
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