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Chemistry - Coggle Diagram

- - - - Collision theory is the theory which explains how reactions happen.
      - When will a reaction occure
        
        For a reaction between two moleecues to happen, they must come close to proximity to each other.
        
        For several a reaction to occur , it must be at:
        
        The correct parts of the molecules must collide with the minimum energy required. this energy is called the activation energy.
        
        Steric factior
        
        The steric factor is the name for the location of the collison
        
        Activation energy
        
        Activation minimum energy is the energy needed for a reaction to happen.
        
        The activation energy is needed to break bonds in the reactants and make bonds in the products.
        
        Bond making ins endothermic whilst bond breaking is exothermic
      - Energy profiles
        
        Energy profiles show the progress of the reaction on the x axis and the energy level on the y axis. this contain
    - - Redox reactions are important in many areas of life as these reactions involve the loss or gain of electrns.
      - OIL RIG
        
        Oxidation is the loss of electrons.
        
        Reduction is the gain of electrons.
      - Agents
        
        Oxidising agents
        
        An oxidising agent is something that oxidises.
        
        It takes electrons from another compound.
        
        It gains electrons in the process
        
        It is reduced in the process
        
        Reducing agents
        
        A reducing agent is an agent which reduces something else
        
        It gives electrons to another compound
        
        this means tha t it loses an electron
        
        It reduces itself.
      - Examples of agents
        
        A + B -> A* + B-
        
        B is an oxidising agent and takes electrons from a. B is reduced.
      - Oxidations states
        
        An oxidation state shows how many electrons an atom has gained or lost in a reactoin
        
        The concept of oxidatoin states is related to electronegativity
        
        Electronegativities can be used to work out oxidation states.
        
        Rules for oxidation sates
        
        To assign an oxidation state in a compound with multiple elements ,.we pretend that each bond is ionic , even if it is not.
        
        We will then ask which element is going to receive the electron pair and this is usually the more electronegative element.
        
        In a compound of fluorine , the fluorine will always have an oxidation state of -1.
        
        The oxidation sate of oxygen will always be negative 2 unless oxygen is in a compound of fluorine whereby Florine takes priority with the exception of the peroxides.
        
        Hydrogen will always have a +1 charge associated with it unless it is in NaH where the state is -1 instead.
        
        In a single compound ion ,the oxydation stae is equal tot he charge of the ion.
        
        in a simple ion , the oxydation state is just the charge on the ion.
        
        in a pure element . the oxydation stte is -.
        
        For transition metals , the oxidation state is shone by Roman numerals/
      - Ionic half equations
        
        An ionic half equation shows weather a reduction or oxidation reaction has taken place.
        
        An example is O2 na + 4e- -> 2o22-
        
        This is an ionic half equation as O2 is reduced to form 2O2-
      - An example
        
        The ion half equation for the oxidation of Ti -> Ti4 is TI-> TI4 + 4e-.