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    (Original post by DaVinciGirl)
    My sixth form adds a half grade higher to our AS grade and then thats your prediction. For AS I've been predicted AAAB (B in physics ). But I reckon I'll probably get maybe AABB. I would be gutted if my predicted grade turns out to be all AAB because of my school.
    lol yeah last year all the subs i did for As at gcse throughout the year i got mostly As and A*s and they still predicated BBBC but i hope they do it differently for A2 cus i need at least AAA as predictions
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    (Original post by Splaffie)
    chem physics and bio but im gunna drop bio for maths because i dont like bio as much and i was always really good at maths, i prefer to explain things in science with equations and numbers anyway im not sure why i didnt take maths in the first place
    lol yeah maths is a good a level i do bio maths chem and spanish would have done physics but didnt want to just do all sciences and physics was my least fav
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    (Original post by GabbytheGreek_48)
    lol yeah maths is a good a level i do bio maths chem and spanish would have done physics but didnt want to just do all sciences and physics was my least fav
    I wish I had taken maths! I took biology, chemistry, Spanish and psychology. Now I can't get into to chem unis
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    (Original post by GabbytheGreek_48)
    lol yeah maths is a good a level i do bio maths chem and spanish would have done physics but didnt want to just do all sciences and physics was my least fav
    I wish I had taken maths! I took biology, chemistry, Spanish and psychology. Now I can't get into top chem unis
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    (Original post by marcobruni98)
    I wish I had taken maths! I took biology, chemistry, Spanish and psychology. Now I can't get into top chem unis
    why u think that u think u might not get the a? or the A* and how do you find spanish i dont rally like the A s level spanish
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    (Original post by GabbytheGreek_48)
    why u think that u think u might not get the a? or the A* and how do you find spanish i dont rally like the A s level spanish
    The problem is top unis require maths for chemistry. Spanish, I have found it okay, we go to Spain quite a bit which helps.
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    (Original post by marcobruni98)
    The problem is top unis require maths for chemistry. Spanish, I have found it okay, we go to Spain quite a bit which helps.
    wow your scool is good taking you to spain never been there but i would love to travel i like the language just dont like the A s sub and oh i see what u mean what top universities we talking about oxford and cambridge im guessing because i think there are still alot of top universities that do chemistry and dont require maths
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    (Original post by GabbytheGreek_48)
    wow your scoo l is good taking you to spain never been there but i would love to travel i like the language just dont like the A s sub and oh i see what u mean what top universities we talking about oxford and cambridge im guessing because i think there are still alot of top universities that do chemistry and dont require maths
    Oh no I go with my family! I find the writing part to be horrendous. And well not just Oxbridge for example Warwick which I have quite nearby also requires maths, I just didn't know I liked it so much at the time.
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    (Original post by marcobruni98)
    Oh no I go with my family! I find the writing part to be horrendous. And well not just Oxbridge for example Warwick which I have quite nearby also requires maths, I just didn't know I liked it so much at the time.
    yeah writing is where i struggle ish but i think more speaking for me and hmm well mayb you could go to a university thats far idk if you would liek that because i know places like nottingham and such dont require maths and they are still top universities or mayb like talk to warwick people and see if they still might accept in some circumstances without maths
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    DaVinciGirl For the 6 marker i explained everything properly but i said how the alcohol has hydrogen bond, aldehyde has dipole dipole attractions and butane has vdw forces but i didnt say the alcohol has hydrogen bonding, dipole dipole and vdws and the same with the aldehyde i didnt say it had dipole dipole and vdws. How many marks do you think ill lose considering that i explained everything well?
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    (Original post by AC12345)
    DaVinciGirl For the 6 marker i explained everything properly but i said how the alcohol has hydrogen bond, aldehyde has dipole dipole attractions and butane has vdw forces but i didnt say the alcohol has hydrogen bonding, dipole dipole and vdws and the same with the aldehyde i didnt say it had dipole dipole and vdws. How many marks do you think ill lose considering that i explained everything well?
    I think the important thing is that it had the strongest intermolecular force, for example when I talked about the alcohol I referred to it as its strongest intermolecular force being h-bonding while butane's strongest intermolecular force was vdw etc.
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    (Original post by neon_reaper)
    I did a very similar question on a past paper (got it wrong so i learnt the answer) and the answer on that was:
    They have the same molecular formula (1) and so would have the same relative molecular mass (1).
    same i said they have the same moleculeas and same number or each atom so they will have the same precise mr
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    (Original post by AC12345)
    DaVinciGirl For the 6 marker i explained everything properly but i said how the alcohol has hydrogen bond, aldehyde has dipole dipole attractions and butane has vdw forces but i didnt say the alcohol has hydrogen bonding, dipole dipole and vdws and the same with the aldehyde i didnt say it had dipole dipole and vdws. How many marks do you think ill lose considering that i explained everything well?
    This is what I guessed from looking at the specimen paper 1 set 2 mark scheme:
    1 mark for writing them in the correct order I believe. 3 mark stating each main intermolecular forces for each molecule and which one is weaker and stronger. 1 mark for staying that more energy is needed to overcome forces for hydrogen bond. And probably another mark for stating how any of them forces occur
    So I'm guessing it will be fine for you doing that as the mark scheme didn't mention the extra vdw for all of them.
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    (Original post by DaVinciGirl)
    But isn't van der waals really the weakest intermolecular force that brings quite easily? Wouldn't permanent dipole dipole overcome the van der waals forces. Not sure tho. Doesn't the alkane only have one extra carbon?
    no VDW is stronger and also carbon chain determines strenth im 100% sure

    e.g in set 2 papers when they are talking about the moleculate VDW is stronger than dipolw, see usually dipole is stronger but this is a weak electronegativity difference betweeen the carbon and oxygen so van der waals is stonger and also cus the butane is bigger too means more VDW btween molecules
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    (Original post by Enderbat1999)
    no VDW is stronger and also carbon chain determines strenth im 100% sure

    e.g in set 2 papers when they are talking about the moleculate VDW is stronger than dipolw, see usually dipole is stronger but this is a weak electronegativity difference betweeen the carbon and oxygen so van der waals is stonger and also cus the butane is bigger too means more VDW btween molecules
    Permanent dipole-permanent dipole interactions are stronger than vdw
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    Guys do you think they'll accept weighing errors when weighing the methanol as a reason why the enthalpy change was different to the data values? And why was the thermometer's uncertainty adequate?
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    Google the boiling point of butane and propanal, kind of a weird question though
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    (Original post by Enderbat1999)
    no VDW is stronger and also carbon chain determines strenth im 100% sure

    e.g in set 2 papers when they are talking about the moleculate VDW is stronger than dipolw, see usually dipole is stronger but this is a weak electronegativity difference betweeen the carbon and oxygen so van der waals is stonger and also cus the butane is bigger too means more VDW btween molecules
    I know what you are trying to say, because in that question they asked why does the molecule still have a lower boiling point even though it has a higher dipole dipole force. But this was to do with butane and propanal (correct me if I'm wrong with the two compounds). Even when you check online for its boiling points, propanal is higher. Some people asked the same in another forum and they said the same that permanent dipole dipole is stronger.

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    (Original post by DaVinciGirl)
    I know what you are trying to say, because in that question they asked why does the molecule still have a lower boiling point even though it has a higher dipole dipole force. But this was to do with butane and propanal (correct me if I'm wrong with the two compounds). Even when you check online for its boiling points, propanal is higher. Some people asked the same in another forum and they said the same that permanent dipole dipole is stronger.

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    ah ok maybe im wronge but do you think ill get atleast 4 marks cus i found the correct bonds and explained only thing i did wronge was the order
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    (Original post by Enderbat1999)
    ah ok maybe im wronge but do you think ill get atleast 4 marks cus i found the correct bonds and explained only thing i did wronge was the order
    Tbh we never know what the mark scheme might be I have attached a picture of some info I found on this AS level chem revision website. I'm sure you'll get 4-5 marks because there's only one mark usually for the order. As long it's the correct info.
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