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    (Original post by Bloom77)
    Omg same!!


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    Just realised co2 has given off isn't an observation fml hahaah
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    (Original post by SirRaza97)
    Haha good chem5 application. That would be pretty hard for an AS sudent xD


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    Hey u postin an update on the Ms. Also missin the name alkene question
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    If you did the working out for mass correctly, but misplaced the units, how many marks would I get? I got 1.065 kg -_-
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    (Original post by j5994)
    Just realised co2 has given off isn't an observation fml hahaah
    Technically it is but I think the correct term is 'effervescence'
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    (Original post by AngryRedhead)
    Technically it is but I think the correct term is 'effervescence'
    do you think I wouldn't get the mark?
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    (Original post by j5994)
    do you think I wouldn't get the mark?
    I can't answer that but I would recommend looking through old spec Unit 1 papers if a similar question comes up and then looking at the mark scheme for that question. If your answer or similar to what you put gets the mark then I would say you have a good chance of getting the mark for it. It was only 1 mark anyway so don't worry about it too much
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    I think you've forgotten the question about empirical formula definition
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    (Original post by SirRaza97)
    Here is my unofficial mark scheme. Anything in bold I am not sure if it's right. So if you have any idea then please tell me so i can add it! If i have missed anything out then aslo let me know!

    Section A

    1.
    a) Relative Atomic mass Definition
    b) Magnetic Field
    c) - Ions accept electrons -Current is formed which is proportional to abundance
    d) Something like 28.065 for the RAM
    e) Similarity= Peaks still at original m/z values becuase +1 ions are still formed. Difference - Peaks at half the m/z values becasue high energy electrons will produce +2 ions

    2. (Can't rmember what topic this was. I think it was about Van Der Waals)
    a) -Electron Density randomly shifts -Creating areas of +ve and -ve charge on molecule - Attraction between molecules which is intermolecular force/VDW
    b) O-H bond big electronegative difference allows for hydrogen bonds. Hydrogen bonds are stronger than VDW.
    c) Fractional Distiallation will sperate these
    d) The Se molecule is larger? This means the VDW forces are stronger between molecules

    3. (Questions about Alkanes?)
    a) Group is alkane
    b) 2,2,4 - trimethylpentane (might accept 2,4,4 - trimethylpentane)
    c) C8H18 + 12.5O2 ------> 9H2O + 8CO2
    d) but-1-ene
    e) C14H30
    f) Thermal Cracking. High temp and high pressure
    g) Isomers question. Chain isomer = H2C=C(CH3)2 Postion isomer = But-2-ene Functional Isomer = Cyclic Alkane so cyclicbutane

    4. (The weird reactions and the shapes question?)
    a) Balancing equation I couldn't remember
    b) Cu2(OH)2CO3 + 4HCl -----> 2CuCl2 + 3H2O + CO2
    c) Effervescense
    d) Something like Cu3O8H2C2
    e) Shapes question - SF6 = Octohedral , 90 degrees -SF4 = See-Saw shape. Lone pair on the horizontal plane. Angles 90, 120 or 180 degrees. Probably will accept -2.5 degrees off each angle.

    Section B

    5. (Period 3 stuff)
    a) - Ionisation energies increase -Increasing proton number - Similar Shielding -Attraction between outer electron and nuclues gets stronger -The bigger nuclear charge reduces atomic radius (I don't think this point is needed)
    b) -Silicon has highest melting point. -Because of macromolecular/Giant covelant structure. -Strong covelant bonds throughout structure. -Requires high amounts of energy to break.
    c) The elements that you could say were Aluminuim because removing electron form 3p shell and Sulfur because of pair repulsion.
    d) -Element Y is Sulphur. -Large jump in eneries from 6th to 7th ionisation enegies -So 7th electron in inner shell so sulphur must be the element Y.

    6. (Calculations)
    a) 0.113m3 (3 sig figs needed)
    b) 1065 Kg or 1.065x106 g
    c) Percentage yield = 49.3%
    d) Method 1 because its 100% atom economy. Only producing one product.
    For 1e i put the similarity as current since they would have the same abundances regardless of ionisation by the electron gun and current is proportional to abundance. are you sure its peaks?

    And ****, i also put the Mr of P4 as just P, wasnt even thinking properly lol.
    I doubt they will accept 2,4,4 since it has to be lowest possible number.
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    (Original post by SirRaza97)
    Here is my unofficial mark scheme. Anything in bold I am not sure if it's right. So if you have any idea then please tell me so i can add it! If i have missed anything out then aslo let me know!

    Section A

    1.
    a) Relative Atomic mass Definition
    b) Magnetic Field
    c) - Ions accept electrons -Current is formed which is proportional to abundance
    d) Something like 28.065 for the RAM
    e) Similarity= Peaks still at original m/z values becuase +1 ions are still formed. Difference - Peaks at half the m/z values becasue high energy electrons will produce +2 ions

    2. (Can't rmember what topic this was. I think it was about Van Der Waals)
    a) -Electron Density randomly shifts -Creating areas of +ve and -ve charge on molecule - Attraction between molecules which is intermolecular force/VDW
    b) O-H bond big electronegative difference allows for hydrogen bonds. Hydrogen bonds are stronger than VDW.
    c) Fractional Distiallation will sperate these
    d) The Se molecule is larger? This means the VDW forces are stronger between molecules

    3. (Questions about Alkanes?)
    a) Group is alkane
    b) 2,2,4 - trimethylpentane (might accept 2,4,4 - trimethylpentane)
    c) C8H18 + 12.5O2 ------> 9H2O + 8CO2
    d) but-1-ene
    e) C14H30
    f) Thermal Cracking. High temp and high pressure
    g) Isomers question. Chain isomer = H2C=C(CH3)2 Postion isomer = But-2-ene Functional Isomer = Cyclic Alkane so cyclicbutane

    4. (The weird reactions and the shapes question?)
    a) Balancing equation I couldn't remember
    b) Cu2(OH)2CO3 + 4HCl -----> 2CuCl2 + 3H2O + CO2
    c) Effervescense
    d) Something like Cu3O8H2C2
    e) Shapes question - SF6 = Octohedral , 90 degrees -SF4 = See-Saw shape. Lone pair on the horizontal plane. Angles 90, 120 or 180 degrees. Probably will accept -2.5 degrees off each angle.

    Section B

    5. (Period 3 stuff)
    a) - Ionisation energies increase -Increasing proton number - Similar Shielding -Attraction between outer electron and nuclues gets stronger -The bigger nuclear charge reduces atomic radius (I don't think this point is needed)
    b) -Silicon has highest melting point. -Because of macromolecular/Giant covelant structure. -Strong covelant bonds throughout structure. -Requires high amounts of energy to break.
    c) The elements that you could say were Aluminuim because removing electron form 3p shell and Sulfur because of pair repulsion.
    d) -Element Y is Sulphur. -Large jump in eneries from 6th to 7th ionisation enegies -So 7th electron in inner shell so sulphur must be the element Y.

    6. (Calculations)
    a) 0.113m3 (3 sig figs needed)
    b) 1065 Kg or 1.065x106 g
    c) Percentage yield = 49.3%
    d) Method 1 because its 100% atom economy. Only producing one product.
    You are a genius bro,i got the same
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    (Original post by Bloom77)
    Omg same!!


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    But there was no cucl4 - it said copper (II) chloride was made which is cucl2
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    (Original post by Charco63)
    So annoyed at myself, I think I just divided 220g by 31 for the Mr of just P not P4😭😭😭 so that'll be why, was the equation definetly not P+02---> P4O10

    Or is it P4+02--->P4010 😩

    I did the same thing man, I was just concentrating on molar coefficients lol, didn't even think about it. Should still get 2 method marks though, i think it was a 4 mark question
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    (Original post by EmmaHarvard)
    Posted from TSR Mobile
    Hey u postin an update on the Ms. Also missin the name alkene question
    not missing anything? i've updated it a few times already. all my answers are not right thats why i left some in bold because idk if it's right
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    (Original post by Jackmilne95)
    For 1e i put the similarity as current since they would have the same abundances regardless of ionisation by the electron gun and current is proportional to abundance. are you sure its peaks?

    And ****, i also put the Mr of P4 as just P, wasnt even thinking properly lol.
    I doubt they will accept 2,4,4 since it has to be lowest possible number.
    dude. i can have some hope xD I put 2,4,4 and i want that mark
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    (Original post by Jackmilne95)
    For 1e i put the similarity as current since they would have the same abundances regardless of ionisation by the electron gun and current is proportional to abundance. are you sure its peaks?

    And ****, i also put the Mr of P4 as just P, wasnt even thinking properly lol.
    I doubt they will accept 2,4,4 since it has to be lowest possible number.
    The question asked about the graph so I assumed it was just peaks. Your argument still remains though
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    (Original post by vinchy)
    You are a genius bro,i got the same
    Then we're both geniuses. Or we are both super dumb...
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    (Original post by SirRaza97)
    dude. i can have some hope xD I put 2,4,4 and i want that mark
    Hopefully then dude xD
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    Did anyone else get 20 something % for the yield at the end?
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    (Original post by SirRaza97)
    The question asked about the graph so I assumed it was just peaks. Your argument still remains though
    ah man you have a point.. I didn't even realise it was just about the graph.
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    Going off this I'm in the mid-high 60s

    Hoping for a similar performance on CHEM2/4/5
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    Me!!!!!! I got 26.4% or something
 
 
 
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