• 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)

Recent content by lara dalal

  1. lara dalal

    Mathematics: Post your doubts here!

    Hello guys. I have a confusion when it comes to drawing argand diagrams, do we draw them as approximations or do we use a compass and protactor. Also do we sketch them on graph paper or on normal paper. Thank you
  2. lara dalal

    Mathematics: Post your doubts here!

    Hi guys I need help in solving q9 part i. Thankyou in advance
  3. lara dalal

    Chemistry: Post your doubts here!

    use m*c*delta T using m as your mass of water (because that is what is actually absorbing the heat) 200*4.18*(55-25)=25080J Now convert that to KJ by dividing 25080 by 1000= 25.08KJ To convert it to KJ/mol divide the 25.08 by the number of moles of the fuel used that is.0326 25.08/.0326=769
  4. lara dalal

    Chemistry: Post your doubts here!

    Here is what I did, Idont know if there is another way of solving it or not. Anyhow this is how i did it. First I found the volume of M in terms of n using PV=nRT (there is no way of actually finding the number of moles because they didnt give you the mass of Helium or its volume) Anyhow Volume...
  5. lara dalal

    Chemistry: Post your doubts here!

    what is the answer?
  6. lara dalal

    Chemistry: Post your doubts here!

    Pressure and temperature increase the rate of BOTH backward and forward reaction, its just that either the forward or backward is increased by a higher amount. In the case of haber process higher temp increases the backward reaction MORE than it increases the forward reaction, hence it shifts to...
  7. lara dalal

    Chemistry: Post your doubts here!

    Arent the Cl atoms in option B also pulling in opposite directions? or does that count as the same direction?
  8. lara dalal

    Chemistry: Post your doubts here!

    I never understood how to know which one has more/less overall dipole. Can anyone explain this to me? The answer is D
  9. lara dalal

    Chemistry: Post your doubts here!

    for option 1 62/100*74 =45.88 of butan-2-ol actually reacted to form butanone. The number of moles of the reacted butan-2-ol are hence 45.88/74(Mr of butan-2-ol) = 0.62 moles. The number of moles of alcohol reacted will be equal to number of moles of ketone formed. Hence mass of butanone is 0.62...
  10. lara dalal

    Chemistry: Post your doubts here!

    there is no C=C for the Br2 to react with. Incase you thought it would react with OH, it wouldnt cause the bromine needs to be added as NaBr and heated with H2SO4 so it can react with alcohol, simple aqueous bromine cannot react with OH
  11. lara dalal

    A level Biology: Post your doubts here!

    I need help in paper3 biology. Does anyone have any websites or anything for plan diagrams and microscope?
  12. lara dalal

    Chemistry: Post your doubts here!

    How could it be C. The OH will combine with the H beside it to get removed as H20 and leave a double bond behind. In C the double bond formed is 2 carbons away from the position of OH. So the OH Could never reach the Hydrogen on that carbon 2 places away from it. In D the OH combines with the H...
  13. lara dalal

    Chemistry: Post your doubts here!

    H3PO4 is generally not an oxidising agent thats why options A and B are wrong. For option C, During the reaction of NaCl and H2SO4, HCl (the acidic gas) is formed, if H2SO4 was a stronger oxidising agent it would go on and form the yellow/green gas of Cl2. but it didnot hence it is NOT a...
  14. lara dalal

    Chemistry: Post your doubts here!

    How do we do this? The answer is A
  15. lara dalal

    Chemistry: Post your doubts here!

    Hello. How do i do this? The answer is D
See more
Top