Flashcards
Chapter 1
Flashcards do conjunto (33)
- 1Mass of: Proton Neutron ElectronProton: 1
Neutron: 1
Electron: 1/1840 - 2Charge of: Proton Neutron ElectronProton: +1
Neutron: 0
Electron: -1 - 3NucleonsParticles in the nucleus of an atom
- 4What are nucleons held together by? What does this cause?Held together by strong nuclear force
Releases large amounts of energy during nuclear fission - 5IonAtom that looses or gains electrons
- 6What is a mass spectrometer?Most useful instrument to accurately measure RAM and amount of each isotope
- 7Which is the only atom with an isotope with an RAM that's an even number? Why is this?Carbon-12
Neither protons or neutrons have a mass of exactly 1 - 8What does a mass spectrometer do?Measures the mass of separate atoms
- 9When is mass spectrometry used in real life?By forensic scientists to identify different substances
- 10How do mass spectrometers separate different isotopes?Separate ions by mass:charge ratio
- 11What are the 4 stages in a Time of flight (TOF) mass spectrometer?Ionisation
Acceleration
Ion drift
Detection - 12What condition does a TOF spectrometer have to be in? Why?A Vacuum
To prevent ions colliding with molecules in the air - 13What happens during the Ionisation stage in a TOF mass spectrometer? (Electrospray ionisation)Electrospray ionisation: sample dissolved in volatile substance
:Forced through fine needle
:To a positive terminal of high voltage
:Tiny +charged droplets
:Solvent evaporates until single positively charged ion is produced - 14What happens during the Ionisation stage in a TOF mass spectrometer? (Electron impact):Sample vaporised
:High energy electrons fired from electron gun
:Knocks off 1 electron from each electron forming a 1+ ion - 15What is an electron gun made from?hot wire filament with a current running through it
- 16What happens in the acceleration stage in a TOF mass spectrometer?+ions are attracted to a -plate and accelerate towards it
Lighter and higher charged ions accelerate faster - 17What happens in the ion drift stage in a TOF mass spectrometer?:Ions pass through hole in -charged plate
:Forms a beam
:Travel along a flight tube
:To the detector - 18What happens in the detection stage in a TOF mass spectrometer?:Ions of same charge arrive at detector
:Flight times recorded
:+ions pick up electron from detector
:current flows - 19What is an isotope?an atom of the same element with the same number of protons and electrons but a different number of neutrons
- 20What is a principal quantum number?The amount of orbitals (shells) an atom has.
- 21What is the Heisenberg uncertainty principle?You can't know where an electron is and its speed and direction
- 22What shapes are the orbitals?s- sphere
d - dumbbell
p - various
f - various - 23What can each orbital contain?2 electrons in an opposite spin
- 24What are electrons?Cloud of charge/wave
- 25What is different about the electron configuration of copper and chromium?Steal from 4s to make 3d
- 26Why do sub-levels overlap?As you get further from the nucleus, principal energy levels get closer together
- 27How do electrons move levels?They are promoted to a higher level by quanta which is a packet of energy
- 28What happens when electrons come back down from promotion?A photon is released which produces colour
- 29Why can zinc not be promoted?It has a full 3d sub shell
- 30What is 1st ionisation energy?Energy required to remove an electron from the outer shell of one mole of atoms in their gaseous state
- 31What is the affect of Charge on nucleus on IE?:More protons
:Higher charge
:More energy needed to remove electron
:Higher IE - 32What is the affect of distance of electron from nucleus on IE?:Bigger distance
:Lower attraction
:Less energy needed
:Lower ionisation energy - 33What is the affect of amount of shielding between outer electrons and nucleus on IE?:More quantum levels
:More shielding
:Less energy needed
:Lower ionisation energy
Informações
- Descrição
- AS level Chemistry (Chapter 01- Atomic structure) FlashCards sobre Chapter 1 , criado por Bethany Westwood em 20-09-2016.
- Criado por
- Bethany Westwood · set 2016
- Atualizado
- 4 jan 2017
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