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    how are you all feeling
    what do you think the 6 marker will be this year?

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    (Original post by bethanystephens_)
    how are you all feeling
    what do you think the 6 marker will be this year?

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    I'm actually a little nervous after the biology exam and I've revised little chemistry!
    I really hope it's something on covalent/ionic lattices..what are u predicting?
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    what is its a method? like forming copper sulphate crystals
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    (Original post by runningcat)
    what is its a method? like forming copper sulphate crystals
    I'm really hoping it isn't!! Although it may, there's a section in my Collins aqa revision guide if u have one on making solvable and insoluble salts
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    i hopr that it is on electrolysis tbh

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    I'm ****ting it!
    Biology is the easiest science and it was so hard

    If anyone knows what formulas we are given please let me know?

    Thanks!
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    I'm hoping it's electrolysis
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    I'd be happy with electrolysis or making salts.
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    I don't know any chemistry
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    (Original post by Lucykx)
    I'm actually a little nervous after the biology exam and I've revised little chemistry!
    I really hope it's something on covalent/ionic lattices..what are u predicting?
    same about nervous thing
    can covalent/ionic lattices its cos I've revised that a lot
    practically the only thing i know
    compared to biology i haven't revised much
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    (Original post by Theen)
    I'm ****ting it!
    Biology is the easiest science and it was so hard

    If anyone knows what formulas we are given please let me know?

    Thanks!
    same !not good at formulas
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    (Original post by breach)
    I don't know any chemistry
    literally i thought i was the only one
    but after hours of revision I'm going to start the formulas i

    im so slow!
    but i understand everything so far
    start revising!
    you can do it
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    Pretty confident with all the topics apart from salts and electrolysis, predicting the 6 marker will be on electrolysis since last 2 years it was making a method and about bonding.
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    You get the list of ions and the reactivity series but no formulas are given
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    can someone pleaseeeeeeeeeee explain electrolysis to me
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    (Original post by chicagokid1998)
    can someone pleaseeeeeeeeeee explain electrolysis to me
    Define electrolysis (2 marks)

    -Separation of an ionic compound into its comprising elements
    -Using electricity

    You may be given copper carbonate - copper has a +2 charge and carbonate ion has a -2 charge, this is depicted on the reactivity series handout.

    The Copper carbonate needs to be in a solution form in order for electrolysis to occur as ions can move
    Metals are generally melted into molten form so that ions can move and a flow of charge can transpire

    the positive ions form at the negative electrode
    the negative ions - carbonate (-2) form at the positive

    think like charges attract,

    this is because the negative electrode wants to give the positive ion an electron so that it becomes the original Cu - copper metal from the copper ion by gaining 2 electrons. it becomes reduced.
    the positive electrode wants to take away electrons from the negative ion, the negative ion becomes oxidised

    at the negative electrode the metal will be produced if it is less reactive than hydrogen hydrogen will be produced if the metal is more reactive than hydrogen, you can see this by looking at the reactivity series

    as copper is less reactive than hydrogen , copper is formed

    the equations are easy to balance and complete, they will ask you to complete ___
    O2- → O2 + ____
    it would need to be 2 O2- this is beacuse there is 2 oxygens on the other side so there needs to be 2 oxygens on this side

    on the right i would need to be e- to represent the electrons lost by the oxygen ion, the number would need to be "4e-" due to the fact that there are 2 electons needed to be lost by each oxygen oxygen ion so it becomes O, there are 2 Oxygens due to "2O2-" which means that there are 4 electrons as 2x2 = 4

    btw, with cryolite,

    Cryolite is used in the electrolysis of aluminium because

    -it reduces the melting point of aluminium
    -meaning that less temperature is required to melt it so it is molten and the ions can move
    -less energy required as less temperature is needed to melt aluminium
    -reducing energy costs

    if the electrodes are carbon just remember that carbon electrodes react with oxygen, if oxygen is being formed at an electrode that is fabricated with carbon then the oxygen will react with the carbon and it will form CO2 and the electrode will slowly vanish c;
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    I want it to be a 6mark question about making salts or strctures!

    How could they ask a 6mark about bonding btw?
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    (Original post by Terrydaktal)
    Define electrolysis (2 marks)

    -Separation of an ionic compound into its comprising elements
    -Using electricity

    You may be given copper carbonate - copper has a +2 charge and carbonate ion has a -2 charge, this is depicted on the reactivity series handout.

    the positive ions form at the negative electrode
    the negative ions - carbonate (-2) form at the positive

    think like charges attract,

    this is because the negative electrode wants to give the positive ion an electron so that it becomes the original Cu - copper metal from the copper ion by gaining 2 electrons. it becomes reduced.
    the positive electrode wants to take away electrons from the negative ion, the negative ion becomes oxidised

    at the negative electrode the metal will be produced if it is less reactive than hydrogen hydrogen will be produced if the metal is more reactive than hydrogen, you can see this by looking at the reactivity series

    as copper is less reactive than hydrogen , copper is formed

    the equations are easy to balance and complete, they will ask you to complete ___
    O2- → O2 + ____
    it would need to be 2 O2- this is beacuse there is 2 oxygens on the other side so there needs to be 2 oxygens on this side

    on the right i would need to be e- to represent the electrons lost by the oxygen ion, the number would need to be "4e-" due to the fact that there are 2 electons needed to be lost by each oxygen oxygen ion so it becomes O, there are 2 Oxygens due to "2O2-" which means that there are 4 electrons as 2x2 = 4

    btw, with cryolite,

    Cryolite is used in the electrolysis of aluminium because

    -it reduces the melting point of aluminium
    -meaning that less temperature is required to melt it so it is molten and the ions can move
    -less energy required as less temperature is needed to melt aluminium
    -reducing energy costs

    if the electrodes are carbon just remember that carbon electrodes react with oxygen, if oxygen is being formed at an electrode that is fabricated with carbon then the oxygen will react with the carbon and it will form CO2 and the electrode will slowly vanish c;
    omg thank you so much. Is this pretty much all i need to know?
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    (Original post by chicagokid1998)
    omg thank you so much. Is this pretty much all i need to know?
    yeah, i sat down at a desk and did all 10 past papers today, back to 2008 :> chaos. Every time the question comes up:

    which of these questions cannot be answered by science alone, explain why

    *tick the appropriate box*

    why: it is based on opinion
    it is an economic/ethical/environmental issue

    also a question on why CO2 has a low boiling point:

    -it is simple molecular
    -there are weak intermolecular forces between the molecules
    -little energy is required to break the bonds
    -meaning that a low temperature will cause it to boil

    or on the structure of graphite

    -made of layers
    -layers have weak bonds between them
    -meaning that the layers can slide over each-other.
    -meaning that graphite is soft or malleable.

    or on diamond

    -strongly covalently bonded to 4 other carbon atoms
    -it is a giant covalent structure
    -the structure is very rigid as there are no layers that can slide over each-other
    -high melting point

    or on thermosoftening / setting polymers

    -thermosoftening polymers do not have crosslinks between the chains of monomers
    -meaning that they can melt and the structure warps

    or why to close the lid on chromatography

    -prevent solvent from vaporating

    or why not to use pen to mark the chromatography paper

    -ink dissolves into solvent
    -smudges and runs up the page
    -affecting experiment

    -
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    (Original post by SuperHuman98)
    I want it to be a 6mark question about making salts or strctures!

    How could they ask a 6mark about bonding btw?
    They could ask about 2 different structures and why their properties are different. In my mock exam they gave us one like this which was:

    Explain why chlorine (Cl2) is a gas at room temperature, but sodium chloride (NaCl) is a solid at room temperature.
 
 
 
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