Hello my fellow A-level warriors. First time on the forum~!
I am from the upper tier
schools and I personally found it manageable and comparable to past
year papers, hopefully it can make up for the egregious numbers of
careless mistakes in my paper 2. My school mates all around did
actually say it was challenging so don't fret if you didn't feel
confident about your answers, hopefully we can all work hard
together for paper 1 which should be the last or last few papers
for most of us next week. Not too sure about calculations though
until the numerical answers are available but the organic
mechanisms were decently manageable. (Haha sir would you mind if
you can post numerical answers for the calculations after you did
the paper)
Did question 1,2,4,5 because I took a quick glance at 3 and
found b and the last few parts of d challenging and decided to give
it a miss and go with the safer option of 2 because I was stumped
at question 5 and only had 25 minutes for the last question but
luckily managed to finish just when the invigilator called for
time.
I think the reduction of esters into 2 alcohol groups may seem
very out of syllabus to us and you have every right to feel
aggrieved that such a question appeared but ultimately Cambridge is
only given our syllabus and learning outcomes so we cannot exactly
blame them for not knowing what is in our lecture notes or not.
Ultimately there were a few clues in the question like one of them
being chiral and L being definitely chiral must mean that M would
not be chiral and hence two similar groups must be present. I
personally did encounter reduction of esters in a 2014 prelim paper
before and was vaguely remembering what is formed, so I confirmed
it by using the degree of unsaturation formula which many schools
have tested before and you would have likely come across it during
your topical practice. There are also many weird questions where
for example we are taught that hydrogenation of alkenes require
high temperature and pressure but in question 5 room temperature is
utilised which contravenes what we learn. So end of the day,
Chemistry is really about applying all our knowledge in some form
or another to be able to counter Cambridge out of the blue tricks
here and there, also I believe the vettors at SEAB are teachers
before and cognisant of what we learn so they wouldn't be so
heartless as not to drop any hints in the question.
For H2O2 I wrote stabilisation by intramolecular hydrogen
bonding as well because I remember Cambridge tested some form of it
last year in the last question of paper 3 I think, not too sure
whether it is the right way to explain but thankfully UltimaOnline
has clarified our worry.
For peroxyethanoic acid I think perhaps the only difference
being an additional O makes the distance to C=O further hence the
dispersal of the negative charge conjugate base occurs to a
lesser extent. Only difference and possible reason I guessed.
Jia you guys don't fret about what is done, some people have
good days and bad days but there is a margin of error for the
higher grades so not too worry. I personally flung paper 2 quite
badly by making numerous careless mistakes.
Also, don't bother about what your friends say, many of them may
be masking their true feelings and deep inside know truthfully how
well they did. Those who gloat and not care about others' emotions
aren't really nice people you should be around then. Remember,
"Those who don't mind (your feelings) don't matter, those who mind
matter". Jia you for paper 1 and your remaining papers.
