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    (Original post by daydream)
    Yah filament it's heated and electrons are excited and can leave the filament which is accelerated towards teh sample to bombard them
    Cheers, but it's titanium, or tungsten?! Something reminds me of T's *shrug*
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    mm i think it's tungsten if i remember correctly.. not titanium tho,no way
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    Talk some chemistry, tell them about your successive IE's and show that you know your subject! [/QUOTE]

    I see ur point.
    Thanks again
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    daydream, HOW OLD R U?
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    (Original post by z!D4N)
    daydream, HOW OLD R U?
    i dun wanna argue with u
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    (Original post by z!D4N)
    daydream, HOW OLD R U?
    Oh jeez, calm children, calm. Can we PLEASE not turn this into the free-for-all like the last Chemistry thread. Fankoo!

    This thread has been useful so far, so shhhhush just zippit.. go and release some frustration

    EDIT: Oh and also.. daydream is on an "AS CHEMISTRY THREAD" .. dya think, perchance, he/she is about 17?! Just err, perhaps.
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    Yes that would be logical
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    (Original post by daydream)
    i dun wanna argue with u
    im not arguing. im trying to ask how old u r. pretending to be an a lv student eh?
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    (Original post by Sahir)
    Oh jeez, calm children, calm. Can we PLEASE not turn this into the free-for-all like the last Chemistry thread. Fankoo!

    This thread has been useful so far, so shhhhush just zippit.. go and release some frustration

    EDIT: Oh and also.. daydream is on an "AS CHEMISTRY THREAD" .. dya think, perchance, he/she is about 17?! Just err, perhaps.
    dude, if u hav time, chek his/her ip and find out who he is... i bet u hes around 40 yrs old trying to pretend to be a student
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    (Original post by daydream)
    Yes that would be logical
    lol, recalling wt i always say eh? thx for learning from me.
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    (Original post by z!D4N)
    lol, recalling wt i always say eh? thx for learning from me.
    er? no?
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    (Original post by z!D4N)
    im not arguing. im trying to ask how old u r. pretending to be an a lv student eh?
    maybe because i am? just becuse i kicked ur ass in some M1 question u think i'm a doctor? :eek:
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    Back to the topic please .

    Can anyone post the structures of the following?

    SO32-, CO32-, NO3-,
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    Can anyone post the structures of the following?

    SO32-
    tetrahedral, 109.5
    CO32-
    trigonal planar, 120
    NO3-,
    pyramidal, 107

    Hope this helps
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    Thanks but can you draw a structural representation with the co-ordinate bonds shown?
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    SO32- is pyramidal
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    (Original post by daydream)
    SO32- is pyramidal
    oh yeah that's right I was thinking of SO42-.
    Sorry about that.
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    (Original post by daydream)
    maybe because i am? just becuse i kicked ur ass in some M1 question u think i'm a doctor? :eek:
    what an author
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    (Original post by Sugaray)
    one of the Mod 1 AQA mark schemes with that question said do not accept 'carry charge' or 'along the layers' or 'move through the metal' so terminology is really important. I put carry the electric charge too cos I can't really think of another way to say it Anyway they put the answer as:

    (Delocalised) electrons
    Move/flow in a given direction (idea of moving non-randomly)
    or under the influence of applied pd

    Ohh really i just knew that they dont accept the "Charge carriers".. Well i am doin the CIE examination .. maybe they are more Generous than the OCR peaple

    (Original post by Sugaray)
    I like that atomic overlapping bit though, never knew that
    u ll know knew Stuff from me all timez ...
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    (Original post by mik1a)
    a) write equation between reaction of calcium with water.

    Ca + 2H2O ---> Ca(OH)2 + H2

    b)When 1 g of calcium is placed in 200g of water, the temperature increases by 12.2 when the reaction is completed. The specific heat capacity of water c , is 4.2JGK
    Calculate the heat releases in the experiment.


    Working with Joules and kilograms (s.h.c. water = 4200 J kg^-1 K^-1)
    ∆Q = mc∆T = 0.2 * 4200 * 12.2 = 10248 kJ

    c)Calculate the standard enthalpy change of the reaction is KJMol for your equation in [a].

    Moles of calcium used (n) = mass/RAM = 1/40
    ∆H*r = -∆Q/n = -(10248)/(1/40) = -410 kJ mol^-1 (3s.f.)

    d) use Hess' law and your results in [c] to calculate the standard enthalpy of formation of Calciumhydroxide.You also need the standard enthalpy of formation of water which is -286KJmol.

    ∆H*r = ∑(∆H*f of products) - ∑(∆H*f of products)
    -409921 = ∆H*f of CaOH - -286
    ∆H*f of CaOH = -409921 -286 = -410 kJ mol^-1

    e)calculate the volume of Hydrogen, measured at rtp, luberated in the expiremnt described in

    moles H2 liberated = moles Ca used = 1/40
    one mole of gas occupies 24 dm^3 at RTP, so 1/40 moles will occupy 24/40 dm^3

    so 0.6 dm^3

    edit - mistakes corrected, thx ram
    Thanks .. just the way i did
 
 
 
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