Flashcards

Chemistry Unit 1

darcy_skye Inglês 8 flashcards

Flashcards do conjunto (8)

1Protons, Neutrons & Electrons
2Isotopes- Same number protons / electrons, different neutrons
- Top number = protons + neutrons
- Bottom number = protons = electrons
3Atomic Models (1)J J Thompson
'plum pudding model'
1897
4Atomic Models (2)Rutherford (& Geiger / Marsden)
1909
- Fired + alpha particles at thin sheet of gold
- PP expected most to be deflected slightly
- Instead most passed through and few deflected back
-Nuclear model to show nucleus and 'cloud' of e-, most is empty space
5Atomic Models (3)Bohr Model
- Same as Rutherford except added that;
- e- in fixed orbit shells
- each shell fixed energy
- e- move between shells and make electromagnetic radiation is emitted or absorbed
- radiation will have a fixed frequency
-- noble gases are inert (can't move)
i.e. with a full shell of e- it is stable and can't react
6Relative Atomic MassAr = mass of an atom of an element
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1/12th mass of atom of C 12 (1)
7Relative Molecular MassMr = mass of a molecule of an element
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1/12th mass atom of C 12 (1)
8Mass Spectrometer (VIADD)Vaporisation - Sample is turned into a gas
Ionisation - Hit with fast moving e- to knock an e- from sample, make it +1 ion
Acceleration - +1 ion directed towards a negative magnetic field
Deflection - light fast moving e- deflected, heavy slow e- aren't deflected
Detection - Ions reach detector, each producing a current depending on the abundance