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    (Original post by DominoMatrix227)
    But part 2 confirmed that the reaction produced heat so it had to be exothermic, so I put my value as negative (can't remember what it was)
    I put -196
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    (Original post by DominoMatrix227)
    Was the actual bond angle greater or smaller than the predicted?
    I put smaller
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    (Original post by DominoMatrix227)
    Was the actual bond angle greater or smaller than the predicted?
    Smaller.. predicted was 109 and actual is 60 (you can kind of imagine it like a equilateral triangle)
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    Same here, was the compound anything other than three carbons?
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    What did everyone put for the 3 stages of the mass spectrometer?


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    For the enthalpy change dont we have to divide it by two as its asking for standard enthalpy that has to be one mole?
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    (Original post by TheAstrocist)
    What did everyone put for the 3 stages of the mass spectrometer?


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    ionisation
    acceleration
    drift region
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    (Original post by shooting_stars)
    I put -196
    So do I, minusing the products from the reactant produced a positive but I assumed because it gave out heat it had to be negative
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    For the Hess law calculation I got -196 but divided it by 2 (because there were two moles but the units are per 1 mole)
    Is that wrong
    Will I get at least one mark?
    I actually put down -196 then changed it because I thought it was a trap and you had to divide by two
    Was the questions enthalpy change of combustion or formation?
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    (Original post by TheAstrocist)
    What did everyone put for the 3 stages of the mass spectrometer?


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    Ionisation
    Acceleration
    Drift region

    PS: I'm not sure if you were meant to say acceleration to same Ek but I included it somewhere in the next point
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    (Original post by shooting_stars)
    Smaller.. predicted was 109 and actual is 60 (you can kind of imagine it like a equilateral triangle)
    Did it ask to give the predicted value or actual?
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    (Original post by ZoeWoah)
    Did it ask to give the predicted value or actual?
    Both
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    (Original post by DominoMatrix227)
    Ionisation
    Acceleration
    Drift region

    PS: I'm not sure if you were meant to say acceleration to same Ek but I included it somewhere in the next point
    (Original post by shooting_stars)
    ionisation
    acceleration
    drift region
    Great, was unsure about that question
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    For the 3 marker (Mass spectrometry) I put:

    Ionisation by removing electrons (so ions are affected by a negative field)
    Acceleration to same Ek
    Heavier ions/isotopes take longer to reach the detector
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    (Original post by shooting_stars)
    Both
    I said predicted would be 109 but actual would be smaller, would i get the marks? :/
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    Q1:
    Mass of e: v.small
    The others are basic

    Ionisation
    Acceleration
    Drift region

    Mass spec, same Ek given to each particle heavier reach later than lighter which is detected by detector and form mass spec graph


    Left gaps so it fits the same patterns

    Beta decay was Se + 2e

    Vol of gas: 277.2/8

    Ar of Ge: 72.7

    Ion in end: SiO3^2-

    Bonding is ionic

    Cloudy as co2 forms precipitate

    NO2 as high temp and pressyre by engine creates right conditions for O2 and N2 to form bonds

    Reforming
    Hydrogen


    Purpose of catalyst to speed up reaction

    2 variables: same mass of metals
    Sams heating time

    -196kJmol^-1

    Bond angle: 109° but actual 104° as corners squeeze the electron clouds.

    Emision spec: descrete E level, e- absorb photon. Excited to higher shell. When return to geound state release photon of characteristic frequency eqaual to E/h. Diff spec for diff elements as diff electron arrangement

    Theres some answers i put down



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    (Original post by Marli-Ruth)
    Me!
    277.9!!!
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    How did everyone do that half life question? I took 3 values (all different) and took an average to get 2.0x10something.
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    (Original post by TheAstrocist)
    Great, was unsure about that question

    for the second stage my mind went completely blank...but I put 'electric field, ions have same kinetic energy'...completely forgot about acceleration..would I still get the mark? :/
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    1.8 for half life

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