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Chem Unit 1 - Coggle Diagram

- - - - eg Period three = 3 occupied shells
  - - - helium
        
        has 2 despite being in G18
  - - - He = 2
      - others achieve octet
    - - because they have already achieved an octet
  - - - s = left
      - d = middle
      - p = right
      - f = bottom
  - - - face some form of supply uncertainty
    - - used in bulk without recycling or recovery
        
        reserves being used up
      - unsustainable
      - deposits concentrated in a small number of countries
    - - new technologies have increased our use of these elements
    - - required for running of society
        
        of significant economic importance
    - - supply of these elements exist in places where there is war and conflict
  - - - measurement of atom size
      - distance from nucleus to valence shell electrons
        
        (usually measured by halving the distance between two nuclei of the same element that are bonded together
      - Dec across period
        
        bcos eff nuclear charge increases and valence electrons are pulled tighter towards the nucleus
      - Inc down a group
        
        eff nuclear charge stays the same but number of shells increases
    - - electron-attracting power of an element towards itself when formaing a chemical bond
      - positive pull comes from nucleus
        
        greater eff nuclear charge = greater electronegativity
      - excludes G18 as they do not readily form bonds
      - Inc Across a period (L to R)
        
        Decreases down a group
        
        number of shells increases but the eff nuclear charge stays the same, so electrons are less strongly attracted to the nucleus the further they are from it
        
        number of occupied shells stays the same but the eff nuclear charge increases to electrons are held more strongly towards the nucleus
    - - energy required to remove one electron from an atom
      - reflects how strongly the valence electrons are attracted to the nucleus of the atoms
        
        the more strongly theyre attracted, the more energy required to remove, higher first ionisation energy
      - dec down a group
        
        constant eff nuclear charge and more shells therefore valence electrons are less attracted to the nucleus as they are further away from it, energy required to remove/first ionisation energy is lower
      - inc across a period
        
        eff nuclear charge increases, number of shells is constant, electrons more strongly attracted to the nucleus so more energy is required to remove it
      - (patterns followed by main block elements)
    - - (repeating pattern)
      - similarity ina groups electron arrangement gives those elements similar properties
    - - also called core charge
      - measure of the attractive force felt between electrons towards the nucleus
      - valence shell electron is attracted to positive charges in the nucleus
        
        repelled by electrons in inner shell
        
        they shield the valence electrons from the attraction of the nucleus
        
        effective nuclear charge = proton # - inner #
        
        eg, Li
        
        1 valence
        
        2 inner
        
        eff nuclear charge of +1
        
        3 protons
      - stays contant down a group
    - - metalloids
        
        properties of metal and nonmetal atoms
      - down a group metals become more reactive
        
        across a period they become less reactive as eff nuclear charge increases
        
        metals readily lose electrons
      - nonmetals readily gain electrons
        
        down a group nonmetals are less reactive
        
        electrons are further from nucleus
        
        across a period become more reactive
        
        b/c eff nuclear charge increases
- - - - made up of subatomic particles
        
        positively charged nucleus
        
        positively charged protons
        
        charge of +1
        
        neutrons (no charge/ neutral)
        
        number of neutrons = mass# - atomic#
        
        both particles together referred to as nucleons
        
        negatively charged cloud of (negative) electrons
        
        cloud gives atom size and volume
        
        1800 times smaller then a proton or neutron
        
        bound to nucleus by electrostatic attraction to nucleus protons
        
        (negative attracting positive)
        
        charge of -1 (equal and opposite to protons)
  - - - number of protons = number of electrons (when uncharged)
  - - - (total mass of the nucleus)
  - - - same number of protons
        
        (atomic number)
      - different number of neutrons
        
        (therefore different mass number)
    - - atoms that have lost or gaines 1 or more electrons
        
        gained gives charge of -
        
        lost gives charge of +
        
        (this is because the less electrons there are the less negative charge there is therefore losing one makes you more positive, gaining one makes you more negative)
  - - - lower energy shells = closer to nucleus
        
        closest = lowest
      - higher energy shells = further orbits
        
        further out get closer togehter
      - Electron Configuration
        
        different energy levels/shells can hold different numbers of electrons
        
        arrangement of shells around nucleus = electronic/electron configuration
        
        each shell has a max number to hold
        
        shell 1
        
        2 electrons
        
        only s subshell
        
        shell 2
        
        8 electrons
        
        s + p subshells
        
        shell 3
        
        18 electrons
        
        s + p + d subshells
        
        shell 4
        
        32 electrons
        
        s + p + d + f subshells
        
        n (shell number)
        
        2 x n^2 = number of electrons able to hold
        
        once a valence shell fills 8 electrons, the other shell starts filling
        
        first 2 electrons go into first shell, next 8 go into second, third shell CAN hold 18 but first fills to 8, excess goes in other shell till its full, then goes back and fills to 18 etc etc
        
        condensed electron configuration
        
        [noble gas in periobefore element] remaining electron configuration of element
        
        Eg. (Phosphorus) 1s2 2s2 2p6 3s2 3p3
        
        [Ne] 3s2 3p3
        
        Exceptions
        
        chromium
        
        fully fills 3d shell first then 4s shell
        
        copper
      - valence shell electrons are the ones involved in chemicl reactions
        
        number of valence e-s correlates to chemical properties
  - - - any orbital can hold a maximum of 2 electrons
    - - each subshell can only hold a certain number of electrons
        
        s = 2
        
        1 orbital
        
        p = 6
        
        3 orbitals
        
        d = 10
        
        5 orbitals
        
        f = 14
        
        7 orbitals
- - - - if that light is passed through a prism it produces a spectrum with a number of spaced out coloured lines or 'emission spectra'
        
        this spectrum is unique for each element
        
        can be used to identify the element
        
        it is 'characteristic'
        
        each line corresponds to light of a different energy level
        
        violet end = high energy
        
        red end = low energy
      - heating an element can cause an electron to absorb energy and jump to a higher energy state (shell)
        
        shortly after, electron returns to ground state (lower state), releasing/ emitting a fixed amount of energy as light
        
        different amount of energy = different colour/ frequency of light
        
        can go in one big jump or many
        
        each jump produces different colours of light depending on distance/ energy released
        
        ground state (all energy released/emitted, lowest energy state
        
        excited state (energy absorbed highest energy state)
        
        energy amount = energy difference between the two levels