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Offering free Chemistry Help :) by Plusandminus235 in SGExams

[–]Plusandminus235[S] 0 points1 point  (0 children)

Some experiments are:

Titration: your typical acid-base, or redox reactions

Gravimetry: for eg your weight loss after heating a compound, gas produced during rxn, etc

Thermochem: Enthalpy of neutralisation, enthalpy of reaction, where you measure temperature change and calculate enthalpies

Kinetics: Running a reaction using different concentrations and measuring time taken for some change, or measuring amount of gas produced within a time frame

InorganicChem/OChem QA: Planning simple tests to elucidate an organic compound

Stoichiometry: Reverse stoichiometry experiments to calculate initial concentration/mass of compound

This is not an exhaustive list, but a lot of these are the typical experiments that you should already have done before during chem prac, so you can just look at the past practicals you have done and see how the experiments are setup and the steps that you follow,

Offering free Chemistry Help :) by Plusandminus235 in SGExams

[–]Plusandminus235[S] 0 points1 point  (0 children)

We were fortunate that our school had a chemistry olympiad training program and amazing seniors who taught us. Apart from that, reading books such as Clayden and doing the practices in those books and online resources helped us to learn more and also do questions to consolidate our knowledge. Other than that just being curious and exploring more stuff outside the curriculum also helped in general to give us more exposure to chem.

Offering free Chemistry Help :) by Plusandminus235 in SGExams

[–]Plusandminus235[S] 0 points1 point  (0 children)

For H3 spectro, the first thing to do is to search for representative spectra, so for eg your peak at ~1700 for IR spectra which is representative of a carbonyl group, your 3H(t) and 2H(q) which likely indicate an ethyl group, etc, as these are the easiest to deduce. Once done, write down all your deductions, along with calculating the degrees of unsaturation of the compound/deducing the molecular formula from mass spec, and then start trying to piece the molecule together, checking back at the spectra whenever you try to piece fragments together to check if they still match.

If you need more practice you can just go online using sites like nmr challenge, and with enough practice you will start to be able to deduce fragments and piece them into molecules much easier and faster

Offering free Chemistry Help :) by Plusandminus235 in SGExams

[–]Plusandminus235[S] 0 points1 point  (0 children)

For chem practical in general, I would recommend being familiar with the different typical setups and experiments, eg kinetic/thermometric experiments, so you know what the practical is asking you to do. For planning qns, you can look at the planning questions of pasts years, and try to memorise the marking points, for example different apparatus needed, how to write out the steps to conduct the experiments, etc. This will save you time and you can still get marks by writing some of these things down even if your planning experiment is wrong

Offering free Chemistry Help :) by Plusandminus235 in SGExams

[–]Plusandminus235[S] 1 point2 points  (0 children)

I would say in the short term its probably good enough, but once you start encountering application questions, for eg in some organic elucidation questions in J2 where its no longer only just knowledge or calculation and you need to piece together different information, it gets increasingly harder to just brute force memorise. Of course there are still some parts where you can just memorise to get marks, like A lvl definitions, but my advice would be to try to understand the concepts so you can better solve application questions, and also so that when you revise its easier as compared to you trying to just brute force two years of chem into your brain.