AQA A-Level Chemistry - Atomic Structure

Cards (38)

  • Plum Pudding Model
    After the discovery of electrons, the theory of atoms by which electrons are located in a sea of dispersed positive charge
  • Sub-Atomic Particles

    The fundamental particles; protons, neutrons and electrons
  • Nucleus
    The central part of the atom containing protons and neutrons
  • Nucleons
    The sub-atomic particles within the nucleus
  • Proton
    A sub-atomic particle:
    - Relative mass = 1
    - Relative charge = +1
    Contained within the nucleus
  • Neutron
    A sub-atomic particle:
    - Relative mass = 1
    - Relative charge = 0
    Contained within the nucleus
  • Electron
    A sub-atomic particle:
    - Relative mass = 1/1840
    - Relative charge = -1
    Surrounds the nucleus in orbitals
  • Strong Nuclear Force
    The force that holds the sub-atomic particles in the nucleus, despite being like particles so should repel one another
  • Electrostatic Force
    The force that holds protons and electrons together in the atom
  • Isotope
    The same number of protons within the nucleus, the same number of electrons, but a varied number of neutrons within the nucleus. The element does not change and is chemically the same due to the same number of electrons interacting with other electrons and elements
  • Mass Number
    Number of protons + number of neutrons.
    Also known as nucleon number (Physics)
  • Atomic Number
    Number of protons.
    Also known as proton number
  • Carbon-14
    A radioactive isotope of carbon
  • Octet Rule
    When drawing electron orbitals, this must be the rule that is considered for MOST elements. e.g. Boron defies this rule
  • Time of Flight Mass Spectrometer
    A device that measures the abundance of isotopes in a sample
  • Vacuum
    The whole TOF:MS is kept under this condition to prevent interference of foreign particles
  • Ionisation
    The sample is dissolved in a volatile solvent and pushed through a fine hollow point needle. This needle is connected to a positive high voltage supply, which rips off electrons from the sample. The solvent then evaporates to form single ions
  • Acceleration
    The positive ions are attracted towards a negative plate. Lighter ions travel faster
  • Ion Drift
    The ions pass through a hole in the negatively charged plate. This forms a bean of ions which travel across a flight chamber
  • Detection
    When ions meet the detector (at different velocities due to their varies masses) the flight times are recorded as they hit a detector which causes a flow of current. This current enables the machine to identify how abundant that mass is
  • Data Analysis
    The signal that is detected is sent to a computer which plots on a graph the abundance of that mass
  • Low Resolution
    A TOF:MS that detects to one decimal place. This is a more common TOF:MS
  • High Resolution
    A TOF:MS that detects to five decimal places. This is a less common TOF:MS
  • Mass/Charge Ratio
    What data is plotted from a TOF:MS
  • TOF:MS
    Abbreviation for time of flight mass spectrometer
  • Overall Isotope Present
    [(m/z1 x abundance1) + (m/z2 x abundance2)...]
    / total abundance
  • Mini-Mass Spectrometer
    A mass spectrometer that investigates a library of spectra to detect chemical weapons, drugs or explosives
  • s
    The first sub-level, can hold 2 electrons
  • p
    The second sub-level, can hold 6 electrons
  • d
    The third sub-level, can hold 10 electrons
  • f
    The fourth sub-level, can hold 14 electrons
  • Arrows
    How to represent electrons in subshells
  • Spin
    Each element in the same orbital must have an opposite -BLANK-
  • Ionisation Energy
    The minimum enthalpy change required to remove one mole of electrons from one mole of an element in the gaseous state
  • Increase
    The trend in first ionisation energies across a period
  • Electron has entered a higher energy sub-level
    The reason for the first anomaly in first ionisation energy across a period. The first ionisation energy has a drop
  • Electron has paired up so has like charge repulsion
    The reason for the second anomaly in second ionisation energy across a period. The first ionisation energy has a drop
  • Decrease
    The trend in first ionisation energies down a group