• We need your support!

    We are currently struggling to cover the operational costs of Xtremepapers, as a result we might have to shut this website down. Please donate if we have helped you and help make a difference in other students' lives!
    Click here to Donate Now (View Announcement)

Search results

  1. xIshtar

    Chemistey Doubts

    Yep, an isotope is exactly that.. As for the earlier question about proteins.. The basic units, amino acids, utilise the amine linkage, NH2.. The proteins consist of a carboxylic acid and an amine.. So, it utilises the C=ONH bonding.. Hope I helped.. :D
  2. xIshtar

    Anyone else get this??

    Heh, I've been studying all through the holiday, doing between 6 and 10 past papers a day.. I still feel like I'm gonna fail though. Also, I feel it is good to procrastinate a little, otherwise you will become bored out of your mind, and out of things to study.. (As I am now :/) Thats an even...
  3. xIshtar

    Chemistry Paper 1 Doubts Here... !

    Not a lucky guess, don't demean yourself.. Call it intiuitive reasoning, sounds much better.. Anyway, I'm open for questions if anyone needs help :D
  4. xIshtar

    All chemistry Doubts here :)

    You know because it's a hydroxide and iron (ii), thus assume that the same rule applies as that with NaOH
  5. xIshtar

    Chemistry Paper 1 Doubts Here... !

    For gary221: 1) B 3) C 4) D 15) D ( I shall explain below) 30) D. Basically, when heat is liberated it means given out. Burning is an exothermic change right, so heat is liberated, Leaving only C and D. The rate of reaction is then increased by a higher temperature.
  6. xIshtar

    Chemistey Doubts

    For 4(b)(ii): 92.3/12 = 7.7 7.7/1 = 7.7 Taking ratios.. 7.7:7.7 => 1:1. For 6(b)(ii): Alkali metals apart from Lithium do not decompose, so the first is no reaction, and the second is calcium oxide + water.
  7. xIshtar

    Condensation polymerisation !!

    H and OH are eliminated from the ends, as it shows continuation, if required.. Basically, if you take the equation for a Polyester.. <> = Main part.. HO-<>-OH + COOH-<>-COOH = HO-<>-COO-<>-COOH Thats for a fixed one.. If you have to show continuation, you eliminate the same thing from both...
  8. xIshtar

    Boring !!!!

    Naw :P
  9. xIshtar

    Boring !!!!

    I'm starting WoW again on the 10th :P
  10. xIshtar

    Chemistry Paper 1 Doubts Here... !

    Both need to have a full outer shell. If XY is the bond made, Y Still needs 2 bonds. Thus it is X3Y or D.
  11. xIshtar

    Chemistey Doubts

    Exactly like that. Sorry, I wasn't checking the thread myself.. Big thanks to Horsepower for going out of his way, so I didn't have to :P
  12. xIshtar

    CHEMISTRY PAPER 31 MAY/JUNE 2010

    Concentration is already mentioned in the example, and I believe it is not acceptable, as the concentration of the acid is given, and may even be required to stay the same. I believe anyway, try checking the examiner report.
  13. xIshtar

    Chemistry Paper 1 Doubts Here... !

    Firstly, assess it's position in the periodic table.. It is at the bottom of group VII.. As you move down the group, colour gets darker, mp and bp both increase, and the states shift to solid. Thus, A is the only acceptable answer.
  14. xIshtar

    chem-- paper 3--- w08

    So the report said what I said? 7(c)(iii) Is perfect, exactly what was needed to be drawn... Considering volume ratios.. 1 : 6.5 10 cm^3 : 65cm^3.. 100cm^3 - 65cm^3 = 35cm^3 For the volume of CO2.. The ratio of volumes is: 1 : 4. 10cm^3 : 40cm^3 => 40cm^3 is formed.. Hope I helped...
  15. xIshtar

    chem-- paper 3--- w08

    Butane is: C4H10, Chlorine is: CL2 So, C4H10 + Cl2 -> CH3-CH2-CH2-CHCL2 +H2.
  16. xIshtar

    Chemistey Doubts

    No, draw the ions with circles, distinguishing between them by placing their symbol inside.
  17. xIshtar

    Chemistey Doubts

    The ionic structure contains ions arranged in a regular pattern, So, positive, negative, positive negative, positive, negative. No two positives should be directly below/above or to the side.. By positive I mean caesium and by negative, chlorine.. So: Cs, Cl, Cs, Cl, Cs, Cl Cl, Cs, Cl...
  18. xIshtar

    Chemistry Paper 1 Doubts Here... !

    Basically, it says what statement is not correct. So, yes, the electrolyte is a dissolve silver salt, and the spoon would be the cathode. Also, the metal electrode would be silver. However, the electroplating does not depend on the reactivity, so A is the answer, as it is the only incorrect...
  19. xIshtar

    guys plz help!!!chem s09_qp3.plz help!!

    The way haochen said also applies, I just thought that this way was easier :P
  20. xIshtar

    guys plz help!!!chem s09_qp3.plz help!!

    I have seen many people ask about Question 5.b) So, I thought I would explain it to everyone here :P From the graph, 8cm^3 of the Phosphate reacts fully with 12cm^3 of T Nitrate. So, identifying only the atoms we need: T : Phosphate Taking a ratio of volumes: 8 : 12 Multiply to find the...
Top