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  • gekpohboy's Avatar
    640 posts since Mar '16
    • 1. Tower Transit

      2. SBS Transit

      3. SMRT

      4. Busways

      5. Woodlands Transport

      6. Go Ahead

      I think Tower Transit got chance, cuz they cooperate with LTA and they emphasise on the welfare of their workers. So Tower Transit is my first choice.

      Next would be SBS Transit and SMRT. SMRT got workers go on strike before, so I'm putting SMRT behind SBS Transit.

      I have a feeling that Go-Ahead may be black-listed because of that interlining incident, and because they insisted on using only B9TL and Citaro for their Loyang bus routes. So I'm putting Go Ahead last.

      Second to last is Woodlands Transport, because they got experience operating 550 buses meh? but at least the welfare is assured, because everyone's Singaporean. :)

      Busways still can consider... so I'm putting it just behind SMRT.

      National Express, Kumho Buslines-Tian San Shipping, Travel GSH-Jiaoyun Group actually no chance, because their business is express bus routes, not city routes.

      Edited by gekpohboy 27 Sep `16, 9:14PM
  • EMERGENCY AMBULANCE
    QX179R's Avatar
    77,118 posts since Feb '08
  • EMERGENCY AMBULANCE
    QX179R's Avatar
    77,118 posts since Feb '08
  • Moderator
    H2 Chemistry @ BedokFunland JC (near VJC & TJC)
    UltimaOnline's Avatar
    8,958 posts since May '05
    • Originally posted by Flying grenade:

      how do u know that hydrolysis of ester is an exo reaction,  the products of hydrolysis have a lower energy content of ester(reactant) ?

       


      The options given are inaccurate portrayals. Also, it's actually the final products (after proton transfer in step 3) that have less energy than the initial reactants.

      Fyi, thermodynamic energy / enthalpy and entropy wise, because esterification and hydrolysis are not redox reactions (the OS of the C atoms are exactly the same pre and post esterification, pre and post hydrolysis), and because there is no dramatic difference in steric strain or resonance stabilization energy in the reactants vs products, as well as number of reactants vs products, any difference in thermodynamic energy / enthalpy and entropy, won't be too dramatic.

  • EMERGENCY AMBULANCE
    QX179R's Avatar
    77,118 posts since Feb '08
  • SMB128B's Avatar
    4,365 posts since May '11
    • Originally posted by SMB145B:

      Maybe convert the Wrights into A95s.

      HAHAHA you funny.

      At most convert specs lor... Masats doors PIS and tuning is all I rly wish for

  • Moderator
    H2 Chemistry @ BedokFunland JC (near VJC & TJC)
    UltimaOnline's Avatar
    8,958 posts since May '05
    • Originally posted by Flying grenade:

      https://www.dropbox.com/s/wvvsxce2hkjff2j/20160927_200958.jpg?dl=0

      why first step higher Ea? both species are not same charged, no repulsion. step 1 involves breaking of a pi bond and forming a bond.

      step 2 involves breaking of a sigma bond

       

      https://www.dropbox.com/s/9x3h7qzb0k6upvd/20160927_201057-1.jpg?dl=0


      Your points are valid, but at the same time, bear in mind that the Ea for the 1st step is somewhat higher than you would expect, due to electrostatic repulsions between the partial negatively charged O atoms between both reactants. The Ea for the 2nd step to cleave the C-O bond is somewhat lower than you would expect, because of electrostatic repulsions between the (partial and formal) negatively charged O atoms in the unstable intermediate.

      Finally, For MCQs, always choose the best answer. Options A & D can be ruled out for obvious reasons. Between C and B (both of which are not an accurate portrayal of the energy magnitudes involved), B is more likely, because in option C, the products are so thermodynamically unstable, that you would unlikely get much alkaline hydrolysis of the ester (despite the non-reversible step 3), and yet you should already be familiar with the fact that alkaline hydrolysis of esters occurs readily (ie. thermodynamically feasible) upon heating.


      Originally posted by Flying grenade:

      how do u know that hydrolysis of ester is an exo reaction,  the products of hydrolysis have a lower energy content of ester(reactant) ?

       


      The options given are inaccurate portrayals. Also, it's actually the final products (after proton transfer in step 3) that have less energy than the initial reactants.

      Fyi, thermodynamic energy / enthalpy and entropy wise, because esterification and hydrolysis are not redox reactions (the OS of the C atoms are exactly the same pre and post esterification, pre and post hydrolysis), and because there is no dramatic difference in steric strain or resonance stabilization energy in the reactants vs products, as well as number of reactants vs products, any difference in thermodynamic energy / enthalpy and entropy, won't be too dramatic.

      Edited by UltimaOnline 27 Sep `16, 8:47PM
  • carbikebus's Avatar
    16,103 posts since Nov '03
  • Moderator
    H2 Chemistry @ BedokFunland JC (near VJC & TJC)
    UltimaOnline's Avatar
    8,958 posts since May '05
    • Originally posted by Flying grenade:

      https://www.dropbox.com/s/wvvsxce2hkjff2j/20160927_200958.jpg?dl=0

      why first step higher Ea? both species are not same charged, no repulsion. step 1 involves breaking of a pi bond and forming a bond.

      step 2 involves breaking of a sigma bond

       

      https://www.dropbox.com/s/9x3h7qzb0k6upvd/20160927_201057-1.jpg?dl=0


      Your points are valid, but at the same time, bear in mind that the Ea for the 1st step is somewhat higher than you would expect, due to electrostatic repulsions between the partial negatively charged O atoms between both reactants. The Ea for the 2nd step to cleave the C-O bond is somewhat lower than you would expect, because of electrostatic repulsions between the (partial and formal) negatively charged O atoms in the unstable intermediate.

      Finally, For MCQs, always choose the best answer. Options A & D can be ruled out for obvious reasons. Between C and B (both of which are not an accurate portrayal of the energy magnitudes involved), B is more likely, because in option C, the products are so thermodynamically unstable, that you would unlikely get much alkaline hydrolysis of the ester (despite the non-reversible step 3), and yet you should already be familiar with the fact that alkaline hydrolysis of esters occurs readily (ie. thermodynamically feasible) upon heating.

  • EMERGENCY AMBULANCE
    QX179R's Avatar
    77,118 posts since Feb '08
  • BusUser's Avatar
    4 posts since May '16
    • Originally posted by dupdup77:

      Yes in Singapore we need fast and effective buses. We need to get to destinations on time. Effective means to reach within certain acceptable time limits. We cannot afford to have slow moving buses and buses not adhering to schedules. Cheers. Thanks. 

      I thought they are slowing down precisely to adhere to regular scheduled intervals?

  • EMERGENCY AMBULANCE
    QX179R's Avatar
    77,118 posts since Feb '08
  • Moderator
    EMERGENCY AMBULANCE
    QX179R's Avatar
    77,118 posts since Feb '08
    • Hello Grabbers!

       

      We would like to be clearer with the previously announced Premier Taxis (Silvercab) booking fee revision. Do note that Premier Taxis (Silvercab) booking fees on our app will be lowered with effect from 1st October 2016.

       

      Here's how the revised booking fees will look like:

  • EMERGENCY AMBULANCE
    QX179R's Avatar
    77,118 posts since Feb '08
    • Baby, Come To Me Lyrics – Patti Austin & James Ingram

      Edited by QX179R 27 Sep `16, 8:37PM
  • Sbs6750E's Avatar
    884 posts since May '15
    • Originally posted by CZT:

      yup im pretty sure is HGDEP but idk trg for wat service :/


      117 and 154 lor. 154 also going HGDEP mah.

  • EMERGENCY AMBULANCE
    QX179R's Avatar
    77,118 posts since Feb '08
  • TehJarVu's Avatar
    114,636 posts since Dec '03
    • going to cook fishhead but but roe and fishhead not totally thawed yet
      hv to wait 15 min hungree die me 

  • Sbs6750E's Avatar
    884 posts since May '15
    • Originally posted by carbikebus:

      S851 HC buses like 3 DDs and 4 bendies leh


      Really meh? Just now camp at Thomson Rd(Aft TPY rise there) from 7-9 am. Only spotted MAN SD and a few bendies.

  • CZT's Avatar
    29 posts since Jun '16
    • Originally posted by Sbs6750E:


      7777 what depot? HGDEP ah? TRG for svc 117 and HGDEP 154 is it?

      yup im pretty sure is HGDEP but idk trg for wat service :/

  • Ganabus's Avatar
    1 post since Sep '16
  • Flying grenade's Avatar
    1,092 posts since May '15
    • how do u know that hydrolysis of ester is an exo reaction,  the products of hydrolysis have a lower energy content of ester(reactant) ?

       

      Edited by Flying grenade 27 Sep `16, 8:20PM
  • EMERGENCY AMBULANCE
    QX179R's Avatar
    77,118 posts since Feb '08
  • EMERGENCY AMBULANCE
    QX179R's Avatar
    77,118 posts since Feb '08
    • 27th September 2016

      Train on EWL: Simei icon_arrow.gif Bedok (037/038)
      Train on EWL: Tanah Merah icon_arrow.gif Simei (213/214)

  • EMERGENCY AMBULANCE
    QX179R's Avatar
    77,118 posts since Feb '08
    • 27th September 2016

      Train on EWL: Simei icon_arrow.gif Bedok (037/038)
      SBS3149L on svc 35 (Bedok Int icon_arrow.gif Alps Ave)
      SG5555X on svc 35 (Alps Ave icon_arrow.gif New Upp Changi Rd)
      Train on EWL: Tanah Merah icon_arrow.gif Simei (213/214)

  • Queen of sgForums
    驚世駭俗醜不啦嘰 moderatress
    FireIce's Avatar
    259,082 posts since Dec '99