AQA 3.12 Polymers REVISION

[@i_love_dua_lipa1]

ur videos r the best, hated organic all thru yr 12 and start of yr 13. currently pulling an all nighter learning from ur vids for paper 2 mock tomorrow. they've helped me so much

[@AaminaAamir]

Omg same I have a mock tommorow that I’m pulling an all nighter for!

[@haroonali991]

Thanks for making these, the Yr 1 revision videos were amazing.

[@AlleryChemistry]

You're very welcome!

[@Masowe.]

33:40 i recycle things at all cost. Even if it means a journey to a recycling centre often or repeating food bits from a foil after cooking or using reusables. I hope people do the same if not better as we need a better environment for our wonderful tomorrow Thank you for the video, i finally understand these things

[@gbxnzz]

yeh but dont forget theres some disadvantages so if everyone recycled there would probably be a higher risk of problems. I think its better that most people recycle rather than everyone. Imagine that one person who doesn't recycle randomly decides to recycle and it was contaminated with other harmful material. It would've been better off if that one person didn't recycle. I think if you are to recycle, you beware what you are doing and handle it properly because some people just do it with no care.

[@kaviyam26]

Concerning the terylene part, i think that there might be a mistake because during the formation of the polyester, -OH is removed from the carboxylic acid while -H is removed from the alcohol

[@Hussein-hp7lq]

thats correct my g

[@Elias.04]

15:20 I believe the repeat unit of Terylene should have another O beside the CH2 on the right hand side.

[@samiultr]

Yeahh i was thinking the same but different sources say different things about the oxygen being removed from which group, whether it's the carboxylic hydroxyl group or the alcoholic hydroxyl group. But I think Allery's diagram is correct as dicarboxylic acid has priority so retains it's oxygen but deprotonates to form the ester bond whilst the alcohol loses both hydrogen and oxygen. Thus, the entire alcoholic hydroxyl group is removed from the right end of the repeat unit whilst the dicarboxylic acid still has it's oxygen

[@jimliu7086]

I also have the same query as @Rishi Ballis Isn't the number of water molecules formed (2n-1) in a reaction forming polyamides or polyesters as the chain ends at some point. Another question is when a polyester is formed surely the water molecule that leaves consists of an oh from the acid and a h from the alcohol from attack, so shouldn't the repeating unit of the polyester have the o bond on the side of the alcohol and on the other side the bond from c, from the c double bond.

[@ashvinkumarathas4486]

Word

[@user-lz8tp9wl7z]

Thank you so much you helped me improve soo much in chemistry!!!!

[@shano8018]

Why is it called 1,4-diaminobenzene not benzene-1,4-diamine

[@AaminaAamir]

I think benzene takes priority

[@marium29]

it can be called both!

[@tomekdavies9529]

Ig its just like amino acids

[@rishiballis7513]

is it meant to be (2n-1)H2O when forming or hydrolysing the polyesters/amides?

[@AS-mw6pw]

The revision guide says 2n. 2n-1 makes more sense though tbf

[@mrvlone2622]

Do we HAVE to know the monomers names forming the polyamide? Or just the polyamides structure

[@mayamikomelmia5511]

Thank you

[@amidiqbal7129]

Does it matter if u remove 2 water molecules or 1. Someone please reply I’ve got an exam in 2 days. Thanks

[@plodys]

Great video! I'm a little confused when it comes to H-bonds. I know H-bonds can form between H-N, H-O and H-F, but in this case we have a hydrogen bond being formed between a N-H and a C=O. Does the H-acceptor just have to have a lone pair?

[@samiultr]

the hydrogen bond exists between 2 polymer chains; where one polymer's delta negative oxygen is hydrogen bonding to another polymer's delta positive hydrogen. There needs to be a lone pair of electrons on the molecule bonding to hydrogen as that's what gives that molecule a partially negative charge. The hydrogen bond doesn't actually include the transfer of electrons as it's not an actual bond; it's an intermolecular force due to differences in polarity (electronegativity) - essentially just a stronger version of a dipole-dipole IMF, that requires the lone pair, not for the transfer, but for the charge

[@lucasonic3461]

NaOH hydrolysis?

[@askeladd6115]

What foods are polyalkanes used in?

[@fahmidahahmed3607]

Thanks so much for this!!!!

[@Masculinity-]

life saver!

[@askeladd6115]

13:05 isn’t an ester link COC? Not OCO?

[@BJM-fn8pd]

No