OCR Salters Chemistry B F332 Advance Notice May 2011 Polymers on the move

OP

Original post by LexxieK

Thanks for these hints! Do you know why polyalkenes are hard to grab and hard to bond? Thanks!

Its due to the loss of the c=c bond during addition polymerisation hence polyalkenes are unreactive. (There is no longer a high level of electron density, for e.g no more pi bonds for nucleophiles to place their attack on)

Reply 42

jakeisthebest

Original post by Hudzy

Started my chemistry revision by making some notes for the advance notice article today, included information suggested by my teacher and incorporated some of the suggestions on here. Hopefully it can be of some use to others.

If you find any errors or have any suggestions of other relevant points let me know. :smile:

I love you <3

If I get an A in this paper I'll buy you a cake.

Reply 43

Polymers on the move.pdf200.7KB

As another TSRian pointed out, the image illustrating polybutadiene polymerisation contained a methyl group. I've edited the image to reflect the polybutadiene included in the article.

Let me know if you find any more mistakes and/or improvements!

Reply 44

OP

Original post by Hudzy

As another TSRian pointed out, the image illustrating polybutadiene polymerisation contained a methyl group. I've edited the image to reflect the polybutadiene included in the article.

Let me know if you find any more mistakes and/or improvements!

Why is there still a double C=C bond in poly(butadiene)?

Reply 45

Toshiya

1

Original post by Hanz_a93

Why is there still a double C=C bond in poly(butadiene)?

Correct me if I'm wrong, but isn't it because when polymers are formed it's when one double bond breaks and the molecules join together? If a monomer has two double bonds when it undergoes polymerisation, one double bond is broken and one is left in it?
And since it's buta-DI-ene, it's got two double bonds.

Anyway, I like this advanced notice article, I'm quite confident with polymers, since the questions you get asked on them are always very similar. Certainly looks nicer than the advance notice from last June, I did that paper as a practice earlier and found the advance notice question to be a complete beast!

Reply 46

Original post by Hanz_a93

Why is there still a double C=C bond in poly(butadiene)?

It's described in the article:
'Polybutadiene is made from the monomer buta-1,3-diene. The polymerisation reaction occurs by the two double bonds opening up, providing linking points to other monomer units and creating a new double bond between the central pair of carbon atoms.'

It's a slightly unusual polymerisation, but as it's described very clearly in the article there's a very good chance that we'll be asked to draw the poly(butadiene) repeat unit.

Reply 47

OP

Original post by Hudzy

It's described in the article:
'Polybutadiene is made from the monomer buta-1,3-diene. The polymerisation reaction occurs by the two double bonds opening up, providing linking points to other monomer units and creating a new double bond between the central pair of carbon atoms.'

It's a slightly unusual polymerisation, but as it's described very clearly in the article there's a very good chance that we'll be asked to draw the poly(butadiene) repeat unit.

Oh thanks a lot man

Reply 48

master_blaster66

17

the january paper is on here
http://www.studentcreche.co.uk/member.php/1-Mr-Online#vmessage76

Reply 49

Original post by pakizrulez

the january paper is on here
http://www.studentcreche.co.uk/member.php/1-Mr-Online#vmessage76

Thanks a lot for that, been looking for it for a while.
I'll upload them on here so people don't have to register.

F332-Jan11-QP.pdf202.6KB

MS_F332_Jan11.pdf199.1KB

Reply 50

bugsymalone

2

Original post by pakizrulez

the january paper is on here
http://www.studentcreche.co.uk/member.php/1-mr-online#vmessage76

Original post by hudzy

thanks a lot for that, been looking for it for a while.
I'll upload them on here so people don't have to register.

thank you

i've been looking for these forever

Reply 51

Although not strictly related to the article does anybody know why poly(ethenol) are insoluble when it has very many -OH groups / hydrogen bonds? It's mentioned in the specification and storyline (though not explained), but there isn't anything about it in chemical ideas.

Reply 52

OP

Original post by Hudzy

Although not strictly related to the article does anybody know why poly(ethenol) are insoluble when it has very many -OH groups / hydrogen bonds? It's mentioned in the specification and storyline (though not explained), but there isn't anything about it in chemical ideas.

If it has too many -oh groups it will form hydorgen bonds within its polymer chains rather than with the water molecules. I think.

Reply 53

sydney07

Original post by Hudzy

Although not strictly related to the article does anybody know why poly(ethenol) are insoluble when it has very many -OH groups / hydrogen bonds? It's mentioned in the specification and storyline (though not explained), but there isn't anything about it in chemical ideas.

In the storyline book page 101, it states that it is soluble in water, and used in hospitals as laundry bags and surgical sutures :smile:

although, yes when there's too many -OHs, like Hanz_a93 said they will hydrogen bond to themselves and not the water :smile:

Reply 54

Original post by Hanz_a93

If it has too many -oh groups it will form hydorgen bonds within its polymer chains rather than with the water molecules. I think.

Original post by sydney07

In the storyline book page 101, it states that it is soluble in water, and used in hospitals as laundry bags and surgical sutures :smile:

although, yes when there's too many -OHs, like Hanz_a93 said they will hydrogen bond to themselves and not the water :smile:

Thank you both.

Reply 55

master_blaster66

17

i still havent read the advanced notice LOOL
slacking :/

Reply 56

Caleb_141

5

Original post by Hudzy

Started my chemistry revision by making some notes for the advance notice article today, included information suggested by my teacher and incorporated some of the suggestions on here. Hopefully it can be of some use to others.

If you find any errors or have any suggestions of other relevant points let me know. :smile:

Mate, I can't thank you enough for posting that up, I always struggle with the pre-release materials and that just covers everything I need to know.

Thanks very much and good luck in your exam (not that you'll need it judging by the quality of those notes) :biggrin:

EDIT: Have to say though that the buta-1,3-diene molecule you have is not correct as it's got a methyl group on one of its atoms, which isn't correct.

(edited 12 years ago)

Reply 57