chemistry unit 1 3.0 / 5 based on 1 rating ? ChemistryASAQA Created by: Francesca RyanCreated on: 30-03-13 11:52 What is an isotope? Isotopes of an element are atoms with the same proton number but different number of neutrons 1 of 17 What is first ionisation energy? The first ionisation energy is the energy needed to remove 1 electron from 1 mole of gaseous atoms to form 1 mole of gaseous 1+ ions 2 of 17 frist factor affecting ionisation energy nuclear charge 3 of 17 second factor affecting ionisation energy distance from the nucleus 4 of 17 third factor affecting ionisation energy shielding 5 of 17 what happens to the first ionisation energies down a group of the periodic table? decresases 6 of 17 what happens to the first ionisation energies of elements across a period? increases 7 of 17 what is the second ionisation energy? the second ionisation energy is the energy needed to remove 1 electron from each ion in 1 mole of gaseous 1+ ions to form 1 mole of gaseous 2+ ions 8 of 17 what are the 5 stages of the mass spectrometer? 1. Vaporisation 2. Ionisation 3. Acceleration 4. Deflection 5. Detection 9 of 17 What happens in vaporisation? sample is turnded into gas using an electrical heater 10 of 17 What happens in the ionisation stage? gas particles are bombarded with high energy electrons to ionise them. Electrons are knocked off leaving positive ions 11 of 17 What happens in the acceleration stage? positive ions are accelerated by an electrical field 12 of 17 What happens in the deflection stage? the positive ions paths are changed by a magnetic field. lighter ions have less momentum and are deflected more than heavier ions. 13 of 17 Whats happens in the detection stage? the magnetic field strength is slowly increased. only ions with lower mass/charge ration make it to the detector 14 of 17 What is the avogadro number? 6x10 23 15 of 17 What is the empirical formula? Gives the smallest whole number ration of atoms in a compound 16 of 17 What is the molecular formula Gives the actual numbers of atoms in a molecule 17 of 17
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