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  1. M

    Zone 4 :p

    Zone 4 :p
  2. M

    Chemistry: Post your doubts here!

    Hmm if the solution does form that means water molecules felt more comfortable forming bonds with the anhydrous aluminium chloride than they did with themselves. All systems want to achieve a lower and lower energy state that gives out heat so they become more stable. If they DID like forming...
  3. M

    A level Biology: Post your doubts here!

    How did it go man? EDIT: Just saw your reply above. Awesome man really happy for ya! :D Hope you get an A* IA
  4. M

    It was fricking hard man. Like I managed to do it but it wasn't one of those papers where you go...

    It was fricking hard man. Like I managed to do it but it wasn't one of those papers where you go "BAM got this one BAM got this one too", each question required time. I normally finish papers in 25 minutes but this one took me 40 minutes. What about you?
  5. M

    A level Biology: Post your doubts here!

    Best of luck bud! :D
  6. M

    Chemistry: Post your doubts here!

    With the Br2 alone, there isn't much of a Markavnikov's rule going. They are all just going to saturate the C=C. And you need not worry about the mechanism if it isn't clear cause it's p1 tomorrow so probably nothing like that will show up. :)
  7. M

    Chemistry: Post your doubts here!

    Wow, nice question. Well that is precisely what happens when you just add Br2 and not HBr. In Br2 since the only atom we have is Br, both Br are attached to the same C=C carbon atoms. However, when we have an HBr, the default programming is that the HBr will split as H+ and Br-, and because C=C...
  8. M

    Chemistry: Post your doubts here!

    Q33: As anastasiagrey113 said, although going by the graph it looks like there is a o point at the origin. Still, that's what "appears" to be the case like when you see a curve that almost becomes and appears to become horizontal but never actually is horizontal if you zoom it up. Similarly, I...
  9. M

    Chemistry: Post your doubts here!

    Q21: These are the 3 isomers I drew up. You should be able to do this. Draw it out on the question paper if you have to. The original molecule was CH2=CHCH=CH2, and you had 2 HBr molecules you could add. So they could be added in this fashion (same order as drawn above) (From left most C to...
  10. M

    Chemistry: Post your doubts here!

    Now to variant 13. Q9: Kc = [products]/[reactants] (each raised to appropriate power from equation) For this equation: Kc = [NH3]^2 / [N2] x [H2]^3 They gave you equation, Kc, and conc. of reactants, so: 2 = [NH3]^2 / [2] x [2]^3 2 = [NH3]^2 / 2 x 8 2 x 2 x 8 = [NH3]^2 32 = [NH3]^2...
  11. M

    Chemistry: Post your doubts here!

    Q30: At first it seems like, "Okay all C=C double bonds means cis trans isomer!" But no. Start by the extreme left C=C. The left C in that C=C has two CH3 groups attached to it, so it doesn't qualify for cis-trans isomerism. The only other C=C is in the middle so that gives us 2 cis-trans...
  12. M

    Chemistry: Post your doubts here!

    Q17: You have to mentally or physically make a note of the equation of hydrochloric acid and calcium carbonate. 2HCl + CaCO3 = CaCl2 + CO2 + H2O In this question, 36/1000 x 0.5 = 0.018 moles of HCl reacted with CaCO3. As per equation, 2 moles of HCl reacted with 1 mole of CaCO3. How many...
  13. M

    Chemistry: Post your doubts here!

    Haha no problem at all, happy to be of help. :D
  14. M

    Chemistry: Post your doubts here!

    Q6: First get the moles of Al2O3 present in the mixture by using the amount of NaOH that was required. Moles of NaOH that were needed = 2 x 100/1000 = 0.2 moles of NaOH. As per the equation they gave us, 2 moles of OH- react with 1 mole of Al2O3. 2 moles of OH- of course means 2 moles of NaOH...
  15. M

    Chemistry: Post your doubts here!

    Q4: The point here is to be concerned with the nucleon number and proton number. They already told you above that in a nuclear reaction, both the nucleon numbers and proton numbers remain constant, i.e. if you add up the nucleon number of the reactants, the sum would be equal to the nucleon...
  16. M

    Chemistry: Post your doubts here!

    H only exists as -1 in very rare circumstances. Not in this one. Here's a tip. If anything is joined to a more electronegative atom, the more electronegative one will take the cake and get the negative oxidation state. For example, N is more electronegative than H so in NH3, N is -3 and H is +3...
  17. M

    Chemistry: Post your doubts here!

    Yeah sure I'll be on and off here too. Good luck man! :) I recommend especially periodicity equations of group 17 and the general oxides etc. as well as the AS Organic equations conditions etc. it's always good to revise them.
  18. M

    Chemistry: Post your doubts here!

    Haha, scary thing is I suck at Chem timing too. The best tip I can give you is what I follow myself. Don't think about revising the paper. Do it with such precision, care, and attentiveness that no need arises for a recheck. I put all my effort in the question I'm doing and once I'm done I...
  19. M

    HOW WAS BIOLOGY P12 M/J 2017??

    It was pretty challenging. Expecting 35 ish (which is bad for me since I always got higher when practicing past papers and in school exams).
  20. M

    A level Biology: Post your doubts here!

    Yeah I managed to do it in 40 mins spent last 20 mins giving it another round. Focus very carefully on the paper don't let anything distract you. If your eyes tire out close them and press them with your thumbs to relax them a bit and get back to the paper. Read each question carefully and try...
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