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lauryn_booth English 9 cards

Cards in this deck (9)

1Describe the Plum Pudding Model of the atomA positively charged sphere with negative electrons embedded in it
2How was the Plum Pudding model proved wrong?By Rutherford firing positively charged alpha particles at a thin sheet of gold foil.
It was found that most particles passed straight through instead of them deflecting as the plum pudding model suggested.
3What was Rutherford's model and what did it suggest?The Nuclear Model.
It suggested that there is a nucleus at the centre of the atom where most of the mass is concentrated. The nucleus is surrounded by cloud.
4Describe the Bohr ModelElectrons can only exist in fixed orbits/shells. Each shell has fixed energy. The radiation will have a fixed frequency.
5What is an isotope?Isotopes of an element are atoms with the same number of protons but different number of neutrons.
6What are relative masses?The masses of atoms compared to carbon-12.
7How can relative masses be measured?Using a Mass Spectrometer.
8What are the four stages of time of flight mass spectrometer?1) Vaporisation: sample turned into gas
2) Ionisation: particles are hit with high energy electrons. Electrons are knocked off the particles, leaving positive ions
3) Acceleration: Positive ions are accelerated by electric field
4) Detection: time taken for ions to reach the detector
9Describe Alpha particles-They're helium nuclei
-Stopped by paper
-Strong ionising ability
-Slight deflection in electric field