Tips for 2015 JC H2 Chemistry Students

Tips for *2012* JC2 H2 Chemistry Students

[Updated on  24 Oct 2013; only grammatical errors corrected]

Hi JC2 students,

If your tutor is nice and hardworking, you may want to request your tutor to give you a few questions of biochem-reduced-to-organic-chemistry. There is a new biochem examiner in the Cambridge exam board, and he/she may set question(s) in Paper 2 and 3. Biochem is becoming very popular in the 21st century and it overlaps easily with organic chemistry.

Or you can hop onto your school library and find some latest organic chemistry university textbooks and scan through just a few biochem-related questions. Just a few will do as your time is highly limited.



You may like to ask your tutor to teach you arrow pushing mechanisms in organic chemistry. This is only fully taught in year 2 NUS/NTU, and has been brought down to A levels in last year's exams. But I suspect your tutor has no time!!! You still need to tackle SPA Planning question! SPA question may be a complete surprise again this year. So there is no point for me in spotting the question. You may just need to prepare the topics holistically.

There is an organic chemistry textbook that is published in 2012 that is written by 3 authors, one of whom is a Cambridge University author. Since Cambridge University examiners set the exams, you may get some clues from this textbook.

Here it is:

Title : Organic Chemistry (2nd edition)
Authors : Jonathan Clayden, Nick Greeves, Stuart Warren
Publisher : Oxford University Press

You may like to briefly scan through it and get prepared to tackle higher order thinking questions in the exams. If you keep cool in exams and extend your knowledge of chemistry concepts, you should be able to tackle novel problems in the exams.
  Please study the section on entropy changes and Gibbs Free Energy thoroughly. School examiners and Cambridge examiners may like to set questions on this section.

You may like to study on chirality - meso compounds. This is in the H3 syllabus but it came out last year in H2 papers.

Mr Maverick Puah, a famous chem tutor in Singapore, has posted sometime ago on his facebook updates on crown ethers. I also favoured this last year, and there is a question which has an organic molecule that resembles crown ether in last year's exam papers. So you may like to wiki on it. But you have to secure your basics first. These things that I mention are the optionals that give you an edge in chemistry.

The examiners are gonna set some NUS/NTU year 1/2 questions in this year's Cambridge papers. So there will be new reactions that you have never seen before in organic chemistry, but they will be an extension to what you have learned before. So keep cool and get your fundamentals right.

HCI / RJC prelim papers this year will be super tough and novel. So you may wanna get your hands on the mid-year exam papers and prelim papers when they are available. Some top JCs are a little short on ideas and may recycle/modify  past year questions. Some neighbourhood JCs have also set tough papers, especially when you get the zealous new graduate teachers who are out to make a difference.


Cambridge may like such acids (which are biomolecules) in their exams:


oxalic acid           HOOCCOOH

malonic acid        HOOCCH2COOH

succinic acid        HOOC(CH2)2COOH

glutaric acid         HOOC(CH2)3COOH

adipic acid           HOOC(CH2)4COOH

pimelic acid         HOOC(CH2)5COOH
  
 and also adipic acid, tartaric acid etc.

<<For more secrets to scoring in A level Chemistry, try tuition with Mr Chong, the blog owner! Contact Mr Chong, the tutor, at 859-one-9710.>>

Please note that there are occasional errors in the solutions of the three Ten Year Series (or five year series).

If Cambridge employs new examiners this year, the style will change drastically again. Be prepared for uncertainties in the chem exams!!



Work life may be more challenging than school life in the Shenton Way area; so cherish your study life. Global situations are really unpredictable in the 21st century. With you going to the workforce in the next 4-7 years, will Singapore still be competitive in 2020?

Listen to your passions and heart. What is your path after A levels? Success in life is about finding your sweet spot and developing in your passion area. A doctor or a teacher or an artist can be very happy serving in a rural area and earning little money.


Organic Chemistry questions are highly likely to take up more than 50% of your prelim exam papers. So prepare adequately for them. Physical chem questions maybe occupy about 30%. This is just a rough guide as it varies from JC to JC (Junior College).

Real tricky Chemistry Olympiad preparatory questions for 2013:

http://icho2013.chem.msu.ru/materials/Preparatory_problems_IChO_2013.pdf 

 Do not worry, your exam papers in Nov 2013 will not be as difficult.

Let me turn my attention to biochem, an out of syllabus subject. Since there is already a biochem examiner in the Chem papers 2012, I might as well dwell on a little biochem.

A lot of the concepts in biochem are drawn from the foundational principles of organic chemistry. 


Biochem : Fats (no, Mr Chong is not fat, though he has been to Macs, BK, MOS burger, Carls Jnr, Texas chicken and KFC. His mum is lean and he may have the "skinny" gene!!!! Lol..... Just a lamey bio joke....)


How are fats (triglycerides) formed? What happens when stearic acid reacts with glycerol? You may want to ask (Dr) Google and key in this acid and glycerol into the search box of Google.



You may want to ask your teacher to teach you about resonance. It is out of syllabus but this term appeared in MCQ 2012 Cambridge exam papers. Also, if your teacher did not teach Williamson ether synthesis, please learn it as Cambridge simply adores it.

There is an old nostalgic examiner who set one of the questions of Paper 2 of Cambridge exams last year. So, they may bring back contents from the old syllabus 10-20 years ago. Already, in 2015 syllabus of Cambridge International (UK), Grp IV elements are back in syllabus, after a long hiatus and disappearance from the syllabus 20 years ago. So you may like to look at the 2014/2015 syllabus at www.cie.org.uk    It gives some clues of the recent trends in Cambridge.

Be adequately prepared. My advice is to have sufficient sleep the day before chemistry exams and be prepared for surprises during the exam. Keep cool, dudes!!!

 

Let me clarify my stand on JC lecture materials and the Copyright Act. The Copyright Act is grossly outdated and some author have argued for an overhaul of the Copyright Act in US in the internet age. With Google and Coursera, my idea is that if every JC puts their lecture and tutorial materials on the website(s) for all to view, students' standards should theoretically be raised. I feel that knowledge should be shared and collaboration is the key to success in the 21st century of uncertainties and seismic changes.

You may desire to analyse the trends in the Cambridge papers of 2010-2012, as your teachers may set questions that are similar to the papers in the prelim exams. Organic chemistry may be extensively tested in May/Jun/Jul 2013.

Pls take note that Cambridge really likes Grp VII elements topic. Though inorganic chemistry seems to be memory work all the way through, there are some trends and tricks to take note of.
  

You may wanna ask your teacher nicely to give your class many organic chemistry elucidation questions. These kinds of questions were hot favorites in the recent papers.

Also, if your class is game for challenge, ask your teacher, if appropriate, to teach your class some H3 / old syllabus S paper / university 1st year organic chemistry. Cambridge is literally operating without a syllabus nowadays. Anything up to PhD level materials can appear. So be prepared. I am just concerned that Cambridge may suddenly increase the level of difficulty in physical chem questions this year. By what means? They just select  some questions from 1st year university textbooks and modify them. It is really an uphill task for students. So master your basic materials and be prepared to do more to get a distinction. BTW, the students before 2008 had it so much easier....

Add to it, only about 20% of the cohort in 2012 achieved an A in chem, according to rumor.

For Paper 2 this year, there may be some chance that either Thermochem or Organic Chem planning question may appear. Thermochem question has not appeared since the new format of the papers were introduced a few years ago. So you may wanna take note. Students are advised to prepare for a holistic and well-rounded education. Spotting questions in A levels may not be useful, since the Cambridge examiners are highly (literally highly) unpredictable.

I have uploaded some questions for both JC1 and JC2 students.

URL:
http://www.scribd.com/doc/127310887/Mole-Concept-Question


2012 Cambridge-Singapore exam papers - organic chemistry questions were quite challenging, so students need to be prepared for a rough it out battle this year.

Ten year series for Chemistry (published by Fairfield Book Publishing) and some other subjects are out in Popular bookshop. Chem TYS costs $16.90. Last few years TYS costs only around $11, but with fewer features.


Set goals for what we want to achieve this year. Set your sight on greater things! Most of your parents and teachers have prepared you well for education, and the rest is for us to overcome hurdles! Next is to be consistent in little things. Your daily habits will determine what your end journey at JC will be. Have an overcoming attitude! Let us be strong!

An important thing is to grasp the gist of every lecture and tutorial. 

You may like to do some physical exercises to prepare yourselves for a challenging year ahead! Also, Being emotionally healthy, eg. not bearing grudges, does help you indirectly in studies as you can concentrate better in studies. Do not worry, be happy!!!! :-)

You can do it! You can surmount the barriers and fly as an eagle in 2013! Your dreams can come true! 

Do plan your CCA activities well, as CCA records are needed for entry to universities and some faculties need good CCA records. Well, it is not just points and grades in CCA. More importantly, is to have passion in your CCA and not just go through the motions. We only have one life, so live it well and to the fullest. :)
 
   What can you do for chemistry? Do you still like chemistry and your chemistry teachers? One important thing is to befriend chemistry and like chemistry and have some passion for this subject, even if you may not touch it the rest of your life after A levels.

** A level chemistry tuition is available. Pls contact (sms) Mr Chong at 859-one-9710 or  e-mail me at chemguide7@hotmail.com


 You may like to revise chemical bonding (a tricky topic), energetics (an important topic) and organic chemistry if you school has started on organic chem. As there is great continuity in the topics for organic chemistry, the minimum you can do is to revise your organic chemistry, as next year's lectures will be booming at higher speeds.

 For those schools that did ionic equilibria, it is a very difficult topic. So revise it and practise a few questions here and there. You can also do mind maps for some of the topics you are unsure of. Using analogies, similarites and differences can be another method to ensure your learning. Ask your school mates for ideas. Collaboration is the key in the 21st century world.


 A good way is to make your own notes, or at least underline your notes. Some of my students draw cute cartoons here and there in their lecture notes....

 All the best! Network with your classmates. You are bound to need help from them at some point or another. Life is mostly about treasured relationships. Grades are not everything. I just wonder what Socrates said about education?????



Time management is crucial in this hypercompetitive education system.

International Cambridge 2012 exam papers are out in xtremepapers.com   You may like to scan through the papers and analyse the trends that the examiners are laying out. The Cambridge Pre-U papers are also out, and are tougher than the traditional Cambridge International papers. Your papers will be more difficult than International Cambridge papers 2012.

I noticed that since 2010 exams, examiners have been using university organic chemical reactions and university level functional groups , just for an example: thiols, -SH, and setting the exam paper in a contextual situation. If the examiner continues the same trend, organic chemistry is going to be atypical this year. So an examiner may take a recent university organic chemistry textbook or his own research interests, then finds some functional groups not in A level syllabus. Next, he finds some reactions in the textbook, and sets the problem. Medicinal (drug) chemistry and biochemistry may be the hottest trends right now. Please note that there is a new Biochemistry examiners in the exam board and the question can get real biochem (cells, carbohydrates, lipids (fats), amino acids, DNA, RNA)
 
The examiners favor structural elucidation problems in organic chemistry. You can find some problems in past S papers (the H3 equivalent before the year 2005). So, you may like to request from your teachers some S papers.



If I am not wrong, a certain government recently used chemical gas to poison some people in their country. The chemical may be sarin gas. You may like to wikipedia for sarin's molecular structure. Cambridge examiners may use news source as inspiration for setting this year's papers.

Apologies if this post seems so haphazard, as this post was written in a span of over 1 year. I just penned my thoughts when I have the inspiration.

 If your school has not finished the entire chemistry syllabus in mid-May, you may wanna read ahead so that you could be adequately prepared for prelim 1 and prelim 2 exams. I know life is very stressful in JC, and this is the price we have to pay for having one of the best education system in the world. So play the game, pay the price and you will be amply rewarded. For those who just wind down from your fun CCAs, pls study very soon as it is late already. If you start studying only in Jun, it may be too late. This is a reminder, and a gentle one! (From one who has seen at least 1000 students go thru this system).

My ex-student who has gotten a Masters in Chemistry did not know of last year's chem papers, but yet told me about the optical activity of tartaric acid when I asked him to suggest two A level questions. Tartaric acid came out in last year's Cambridge papers and he was spot-on.

Another question he suggested was on enzymes. So you may wanna study Chem kinetics - enzymes and also proteins in organic chemistry. Sometimes, intuition can prove to be better than logic.

Lol.....


There are advantages of studying in a neighbourhood JC. The JC schoolmates are usually more down to earth and maybe more friendly and sociable. There are intelligences and talents that the O level exams and CCAs do not measure. BTW, One elder has said that some professors, who are highly specialised in their fields, may know less than some taxi drivers in UK in certain fields which are not their expertise.

Perhaps, it may not be the top scorers in the exam systems that do well later in life. I know of some adults who had less than an O level certificate and are now close to millionaires.

Anyway, how does one measure success? In terms of money, status and power? Is that the right way of measuring people? This question begs a debate. Our Singapore system may have too narrow a definition of success.

Anyway, there are many neighbourhood JC students who are fulfilled in their careers and family. Some are late bloomers. So, I propose to the readers that there is a social intelligence that the neighbourhood JCs cultivate that enables the person to survive well in society. Anyway, what I say is debatable and a more statistical sociological study is needed to justify my point.

Just my two cents worth of thoughts.  

[Updated on 20 Apr 2013]

I shall be posting new trends in the coming months perhaps after Cambridge has set its papers.

Look out for this new post:

 http://alevelchemistrysg.blogspot.sg/search/label/%23%20%5EUpdated%20Tips%20for%20*2013%20JC2%20students

 I shall be beefing this new post up in the coming months. Already, there are some food for thought in this new post : tips for 2013 students.

Excerpts from this new post:

(Updated on 26 Apr 2012)




There is an old nostalgic examiner who set one of the questions of Paper 2 of Cambridge exams last year. So, they may bring back contents from the old syllabus 10-20 years ago. Already, in 2015 syllabus of Cambridge International (UK), Grp IV elements are back in syllabus, after a long hiatus and disappearance from the syllabus 20 years ago. So you may like to look at the 2014/2015 syllabus at www.cie.org.uk    It gives some clues of the recent trends in Cambridge. Be adequately prepared. My advice is to have sufficient sleep the day before chemistry exams and be prepared for surprises during the exam. Keep cool, dudes!!!


Study life was the happiest times in my life. There were friends to joke around, books to accompany me, and music to enliven me and cheer my spirit, and computer to do my programming on (say yes to the ancient C programming!!! Yeah!!!!)... Those were the happy days....

Pardon me for my crappiness (is there such a word???). With ageing, I am getting long winded and naggy....

Lol..... Lol..... Haha.....
  

(Updated on 24 Dec 2012)

[This post is closed]

     

If you have the time, you  may wanna practise 2010/2011 International Cambridge chemistry papers at xtremepapers.com , just in case Cambridge sets similar questions from that paper. BedokFunland JC tutor has claimed that Cambridge modified some of the International chem papers of 2010 and 2011 in Paper 2 and 3.

I think I mentioned before [CuCl4]2- ions before in this post; Cambridge may have set a similar ion [PbCl4]2- in either Paper 2 or 3.

Thank you everyone for journeying with me in 2013. What a year! May it be an enriching year for you.

It is my pleasure to serve you all in these blogs.


All the best for your future endeavours!


Actually, arrow pushing in mechanism is only properly taught in NUS / NTU 2nd year. Cambridge has really raised the bar for A level chemistry exam!


One of the students said that organic chemistry for Paper 3 was quite hard. As one tutor has said, too many students apply for medicine and law faculties so Cambridge has to set a hard paper to differentiate the high A scorers, low A scorers and Bs and Cs grade students. But bear in mind that grades do not determine the worth of a person. Academic success is not really directly correlated with success in life later on.

Had your Paper 3? Apologies if many of the topics I suggested to you in this post did not come out, as Cambridge is almost impossible to predict in the recent years. Anyway, if you had delved deeper into the topics I suggested, the concepts reinforce each other and there is a synergistic effect upon your H2 Chemistry. Usually H3 chemistry students find that their organic chemistry improves as they are exposed to an enormous amount of reactions and some mechanisms.

Please do not underestimate Paper 1! It takes up a sizeable percentage of the overall marks in all papers. It is gonna be tricky and some questions will be from university first year textbooks.

The bar has been raised. But say you can! You can! You can! Just do it!
   

All the best to your Paper 3! Pls read through all the 5 questions carefully and eliminate the question which you feel you may not score very well in. Time management is crucial. You need to be concise in your descriptive answers and yet the key words have to be in the answers. Do the calculation questions carefully as the different parts of the question are usually interlinked.

To prepare for Paper 3, you may wanna read some of Ultimaonline (aka BedokFunland JC) website for some of the FAQs. These questions are reflective of the latest trends of Cambridge questions. His answers are generally pitched at JC2 and NUS/NTU undergrad year 1 standards.

His website can be found at the right side-bar of my webpage. All the best!

You may want to have sufficient sleep before the paper. You need a very clear and alert mind for the atypical questions in Paper 3. Hopefully, it is a little easier than 2010 and 2011 papers. 

Chem Paper 2:


I think I guessed correctly for clock reaction (slow disappearance of the color of solution when mixing two reagents, eg. hydrogen peroxide with potassium mannganate(VII)), mentioned below, which I wrote some time ago.

There is a question on sulfur and sulfur dioxide, which are reagents for the Contact process of manufacturing sulfuric acid (I guessed correctly in the tips below). This was in the chemistry syllabus twenty years ago! The examiners are really nostalgic!! [Meanwhile, Play some Beatles song -- They wanna hold your hand. Lol.....]


 


So, you can roughly spot what topics may not appear in Paper 3. Those topics that appeared in Paper 2 may not appear or appear less in Paper 3. However, organic chemistry is likely to appear for at least 3 of the questions in Paper 3. They love alcohols till nitrogen compounds and proteins  topics. Carbonyl compounds are sure to come out in Paper 2 or 3.





All the best! 

I was curious and googled on LCD screens. Your older LCD screens may contain the toxic gas nitrogen trifluoride (NF3). Try drawing the Lewis structure of one molecule of this. Illustrate with a diagram why one molecule of NF3 forms intermolecular hydrogen bonding with a molecule of methanol. Why does NF3 form in a 1:1 ratio with BCl3?

My laptop should not be in my bedroom! Lol....!!!!

BTW, someone in Russia mistook methanol for ethanol, and drank the methanol. He was rushed to hospital. Methanol in sufficient quantity can make one blind.

Talk about funny and dangerous chemistry. Anything wrong with the environment, it must be due to the chemists....


(Updated on 31 Oct 2012)


 
Information for
those aiming for a distinction in H2 chemistry in the year 2012:

This section is a joint project between BedokFunland JC (http://infinity.usanethosting.com/Tuition/) and myself.



Thank you BedokFunland JC for your invaluable advice!


[New] May the blessings of Heaven be with you. God bless you richly. You CAN do it!

[New] All the best to your exams! Revise your theory topics and SPA topics, and practise Cambridge-Singapore papers, starting from the latest papers to the earlier ones.

[New]  An experiment on extraction of organic molecule citral from lemongrass. Partition coefficient and solvent extraction are involved. You may want to scan through the theory and look at the procedure:

http://spot.pcc.edu/~chandy/241/steamdistillationnew.pdf


[New] Another experiment on extracting an organic compound from nutmeg:

http://www.buzzle.com/articles/extraction-of-trimyristin-from-nutmeg.html
 

[New] Would you like to take a look at trial Chemistry Olympiad 2012 questions? You may wanna look at page 49 onwards where there are questions like SPA planning as in your Paper 2. You may also look at the organic chemistry questions. Be reminded that the questions are quite tough.

http://www.scribd.com/doc/93843456/44th-International-Chemistry-Olympiad-Preparatory-Problems


[New] Do you know how to draw the Lewis structure of HgC2N2O2? Wiki for mercury fulminate to check the answers.

Proteins, enzymes (remember kinetics has a small section on enzymes?) and supramolecular structures are the hottest issues in chemistry right now. Biological systems are tighly integrated with chemistry at the research level.


[New] Just in case you would desire to attempt International Cambridge papers, which is of a slightly different syllabus, and generally much easier than Singapore papers:
xtremepapers.com

I am not sure of the safety of the website, which may have malware.


[New] Maybe you like to re-do the Cambridge exam papers from 2007-2012. If you can grab hold of the prelim papers 2013, you may like to try a few of them too. Look at HCI, RI, and YJC papers as a suggestion, and look how they are similar or different. Can you pick up any trends?


[New] Maybe the strategy now could be to brush up on the theory aspect of weaker topics and to practise lots of Singapore-Cambridge exam papers, and a little prelim papers (if you can grab some 2013 prelim papers, if not 2012 papers).




[New] Able students may like to scan through Indian Chemistry Olympiad 2012 competition (questions set by Indian professors). (Google for Chemistry Olympiad 2012 questions). The international papers need to be purchased from rsc.org
Very interesting, indeed!


Let me send you an e-Cappucino to chill a little. ^.^
http://t0.gstatic.com/images?q=tbn:ANd9GcTHdcu04yVrXSAD8Mx1NuYylzOEiyobrXOSl9doNRzqVfb7TFwP6w

[New] Previously, I mentioned about the new genre of swimming materials used in World swimming championships. A swimmer wore a new generation polyurethane swimsuit and beat Michael Phelps to the 200 metre freestyle in Jul 2009. Hope that Phelps may not go into gambling addiction.

Read about polyurethane in wikipedia:
http://en.wikipedia.org/wiki/Polyurethane#Chemistry




[New] You may like to study the effects of dilute aqueous ammonia and concentrated aqueous ammonia on chloride, bromide and iodide ions. This is found in the chapter of Group VII and also ionic equilibria.

[New] Chemical equilibria is very likely to come out, and it may involve Kp of gaseous systems.

[New] Will Cambridge like H-O-N=O? Or HClO3? Or CNBr? Or H2C=N-H? Or Br-CN? Or NOCl? Or C2O4 (2-), HC2O4(-), H2C2O4? Or AgIO3? Or HClO4? Or Ag3AsO4? Or NH2OH?



[New] Not sure whether global warming may come out in exams? Do you know the greenhouse gas (GHG) nitrous oxide (laughing gas) N2O has chemical structure N=N=O? Try working out the dot and cross diagram. Can you name three greenhouse gases?

[New] Now that prelim exams is over for some of you, you may want to find out your weak topics and revise the concepts, and practise basic or advanced questions to capture your learning. Time is precious, so optimise your time.

[New] I have just seen the International Cambridge Jun 2012 papers, and they are not too difficult. You may be a little relieved. But, Singapore-Cambridge papers will definitely be of higher standards (Nov papers are more difficult than Jun papers). A little of what I mentioned in my tips post and proteins question (sickle cell anaemia) came out in the Jun papers.


[New] Are there anything special about the bond lengths of the C-C and C=C bonds in buta-1,3-diene? Wiki- about this molecule. (Topic: delocalisation of electrons in diene compounds)


[New] Those who have a little time to spare and are game for the challenges, you may desire to practise John McMurry's Organic Chemistry textbook questions, especially those of the later chapters, eg. hydroxy compounds, ***** carbonyl compounds *****  . O level papers have gotten tougher with A level questions introduced, hence we would expect to see some simplified uni chem questions this time. One recent BBC report says that one UK exam board marked the English papers more strictly. And less A* and A grades were awarded for one exam board. Well, talk about globalisation and its effects.... You are still up to the challege!!! Our brain structures are complex enough to adapt and generate new neuro-connections.




[New]   News: Research institute develops longer-lasting fuel cell catalyst


http://www.channelnewsasia.com/stories/singaporelocalnews/view/1221844/1/.html

[New] Cambridge may like such species in their exam papers:


"Heating magnesium carbide in nitrogen produces magnesium cyanamide:


MgC2 + N2 --> MgNCN + C


Draw the dot and cross diagram of C2(2-) ion and cyanamide (NCN(2-) ion. "


Do you happen to know the dot and cross diagrams of cyanate, isocyanate, thiocyanate, chlorate(V), chlorate(VII), chlorate(III) ions, iodic acid and hypobromous acid? Wiki for these species.


How about types of hybridization of non-hydrogen atoms in CH3CN and HN=NH molecules?


Compare pKa of EtNH4+ and Et3NH+ ions where Et stands for an ethyl group.


[New] Carbon suboxide, or tricarbon dioxide, is an
oxide of carbon with chemical formula C3O2 or O=C=C=C=O. (Courtesy of www.wikipedia.org) Will Cambridge like such molecules? It has come out before in the papers. It is your guess and my guess. 

Some students sabotage themselves by telling themselves subconsciously they do not like a particular subject. It is no wonder they do not excel in the subject. Excellence begins in the mind-set and paradigm. You can do it.... Just do it.... And do the right thing....!!!


[New]  Novel membrane (using nanofibres) distillation technology for desalination unveiled :

http://www.channelnewsasia.com/stories/singaporelocalnews/view/1221131/1/.html

[New] If you can finish all of 2012 prelim papers of all JCs, the chances of you getting an A or a B may be higher. It is all about making few mistakes in exams and getting the right answers for the examiners that matter. Interpretation of question is an important key to scoring in the exams. We need not be long-winded in our answers. (You may find me super-duper long winded, haha....)


[New] You may wanna look at spider silk (a protein that has beta-pleated sheets).


Spider silk
http://www.chm.bris.ac.uk/motm/motm.htm
http://www.xs4all.nl/~ednieuw/Spiders/Info/spindraad.

** You may wikipedia on "Zinc as an enzyme cofactor ", "Partition coefficient" in chromatography, "biofuels", "Ion channels in biological membranes", "Sickle cell anaemia", "Plastics that conduct electricity or emit light", ****"Ionic Liquids"******.


 [New] For organic chemistry mechanisms, you need to learn them well and reproduce them almost perfectly in the exams. Organic chemistry is understanding first, then memory work is next. In a chemical reaction, first understand which functional groups are changed as you go from reactants to products, and identify the nucleophile, electrophile or free radical, and check whether it is a substitution, addition, elimination or etc.... reaction. Lastly, it is to memorise the reaction conditions and catalysts. There are usually reasons why certain catalysts are used in certain reactions.





[New] You may wanna google for Ni(CO)4 (nickel carbonyl complexes). I saw a question that appeared in HCI test papers. Cambridge may test on substances only encountered in research papers this year. Tell yourself you are intelligent and you can conquer all the papers. Be Prepared!!!


JC2 students, you had your chemistry exams right? Some may have a wake-up call. It is time to study real hard and study smart. The tips below are for those who have done their basics and wanna score real well for chem exams.


[New] : You may wanna grab hold of mid-year assessment papers of HCI, RJC, VJC and others and look at the standards.. Wake up call for some?





Just to pre-empt you: prelim exams will most probably be tougher. So buck up and let us go on this journey together. Once you finish A levels, you will be amazed how far you have gone! Secure your organic chemistry!!!


[New] We can learn from sports psychology. Michael Phelps, the great swimmer, psyches himself up before every race. So, similarly this A levels assessment is also a mind and psychological game. Even if the exam is tough, psych yourself that you will be     tougher     than the others. You have the resilience. Confess good words. Declare yourself a victor and celebrate (a little) victory even before the exams is coming. Being emotionally healthy is highly important. Inject yourself with doses of good and inspirational words : "I will conquer! I am a victor!"


For those who are a little knocked down before, get up. It is time to get up. Time is precious. Redeem the time. Get up! And keep fighting! Surround yourself with positive people! It is a mind game. Get up and start fighting. It is a mini war. Like a boxing match, the one who lasts the longest and is not out of the ring wins. Get up!


There are motivational books and inspirational websites. Get your morning happy. Mornings are the most crucial moments of the day. Get yourself psych up. You know the methods yourself.


Confess good words and positive thoughts.

Religion is a powerful force. Those who are open can seek help from the Person Upstairs.



-------------------------------------------------

For the extraction of caffeine (a possible Paper 2 planning question), pls look at : https://teach.lanecc.edu/thompsonj/CH241/laboratory/Caffeine%20Extraction.pdf

[New] You may wanna purchase HCI Organic Chemistry Summary booklet or do summary reactions for each functional group in organic chemistry. 


How to tackle organic chemistry


For organic chemistry, first understand the mechanism behind the reaction, then check the before and after (reactants and products) to see the which atoms or functional groups have been changed. (A little like the slimming ads where you compare the person before and after slimming. What changed before and after????) Lastly, understand why the reaction conditions are used. Then, "memorise" the reaction conditions. Many of the reactions require heating or reflux.


For some chapters, you need to know the details of the mechanisms very well. It requires some knowledge of nucleophiles, electrophiles or free radicals and the electron flow (eg. electrophilic or nucleophilic attacks). Next is to know whether the reaction is an addition, substitution or elimination or even redox reaction. (or other types of reactions)


After understanding the reactions, next is to commit into memory the reaction conditions and to practise as many questions as possible.


[New] I went to National Library on a hot and humid afternoon and scanned through about 10 issues of Nature journals published in 2010. Cambridge examiners may draw ideas from these issues.


What I found was that the main articles that were of interest are of the following topics:


Nanoparticles (nano-ribbons, nano-wires, nano-clusters)

 - Iron, Indium, Arsenic, Gold, Silver nanoparticles

Atmospheric chemistry 


Semiconductors


***** Graphene (an allotrope of carbon. I suggest you wikipedia on graphene, it is a little similar to graphite)


Enzymes and proteins in biochemistry and medicine


You may try to source for Cambridge International Chemistry Papers 2011 and even Jun 2012 if they are available. Clues can be obtained from there.


I have looked at Nature.com, a prestigious journal on science and medicine, and I found that in April's issue, liquid crystals were featured in that journal. Basically, the concept is that an organic molecule can interconvert between one isomer into another, and (uv) light absorbance is altered as the conversion is done. This is one way that liquid crystals can be made. Nowadays, many spectacles can change its tint when exposed to sunlight. I believe it works by a similar principle.





*****
http://www.bbc.co.uk/news/education-17854008

http://www.telegraph.co.uk/education/educationnews/9228904/A-level-maths-content-being-dumbed-down-claim-experts.html

Pls scan through these latest news in Apr 2012. Maybe this year's science papers may have more and tougher calculations. Just hope that derivations of equations will  not come out (There are some in Kinetics and Ionic Equilibria). You may need to work on Transition metals chemistry mole calculations and ionic equilibria calculations etc.


[New] 2013 Chemistry papers may be highly unpredictable as Cambridge International is under a lot of fire from All sides in UK. Learn like the scouts, Be Prepared!


******* Understanding chemistry is not to memorise the whole chunk of notes. Smart students ask themselves what the concepts are: eg. electron flow, arrow pushing, guessing which gases or other products are generated in a chemical reaction (smart guess), summarizing notes in their own words. Some students think of wacky short-cuts to help them remember concepts. (Thanks, Adam Khoo LTG!) Also, a visual learner may use a lot of highlighter and mind-maps, diagrams, tables and charts and summary of reactions and their reaction conditions to help them remember. 


One of my students who was hungry for success remembers by keywords and association (neuroscience technique). Ask your smart classmates for some tips. Be nice!



A very useful advice from rsc.org (a chemical society) for tackling Paper 3 of Chemistry exams:


"Some of the questions will contain material you will not be familiar with.
However, by logically applying the skills you have learnt as a chemist, you should be able to work through the problems. There are different ways to approach the tasks – even if you cannot complete certain parts of a question, you may still find subsequent parts straightforward. "


*** For those JC2s who are really struggling in chemistry, please try to get your foundational topics right. Ask for help from your classmates. You may also wanna seek help from tuition centres or private tutors or internet forums. Or e-mail to openlectures.sg and ask if the scholars can help you. Please start to revise now! Time and tide wait for no man!


**** I wonder if there are new A level chemistry textbooks newly approved by Cambridge International board? The textbooks may be written by current chemistry examiners. If your friends could band together to purchase the new textbook, it may help a lot! Style of exam questions may be similar to the textbooks. I shall check this out or can someone comment below? There is a Cambridge chemistry textbook on sale in Popular Bookshops. Not sure if your classmates and yourself may like to buy it collectively. Teamwork helps!


* News in Apr 2012: You may like to look at bio-inorganic molecules, such as haemocyanin, myoglobin, haemerythrin, cytochromes P-450 briefly as I suspect that one of the examiners has training in bio-inorganic chemistry. Please use wikipedia or refer to an inorganic chemistry textbook in National Library or your school library. 


**** Drawing inspiration from Rod Beavon's chemistry site, you may wanna look at esters, fats and oils. Also, you may like to scan through Nuclear Magnetic Resonance Spectroscopy (NMR) and Infra-Red Spectroscopy (IR) theory. Cambridge set questions based on this website in 2010 and 2011 papers.


Last two years (2010 and 2011) H2 Chemistry papers have been tough and atypical from normal tutorial questions and prelim questions from many JCs.


One sources says that this year's papers may even be tougher. So come prepared! Some of the national exams papers may be highly atypical, very different from prelim papers. Anyway, another source says that it is all graded on a *Bell Curve*. So keep cool, and practise a variety of questions from various sources.


See my post on analysis of 2011 Chemistry Papers:
http://alevelchemistrysg.blogspot.com/2012/02/analysis-of-2011-chemistry-9647-papers.html 

For 3 challenging exam style questions (mainly on organic chemistry, pls see :
http://alevelchemistrysg.blogspot.com/2012/03/fun-questions-inspired-by-research.html )

For a  fun proteins question, pls refer to my blog's side-bar. Proteins are almost 100% guaranteed to appear in your school's assessment or in the national exams. 


Btw, you may wanna take a look at recent Round 1 Chemistry Olympiad questions to get a feel of the trend of chemistry exam questions. The Olympiad questions are much more difficult than A level exams but you may wanna look at the style of the questions.

URL : http://www.rsc.org/Education/events-and-competitions/Olympiad/olympiad-questions-answers.asp 
Also, the real Olympiad competition questions are way more difficult than the Round 1 questions posted in the link.

Good Knowledge to learn if you are aiming for a distinction in chemistry:


Stay cool! (: It is a long list, but you may just wanna study some topics. Chemistry fanatics may spend much more time on the advanced A level topics!



Cambridge may set questions based on compounds found in soil and rocks. 

A soil question came out in O level chemistry exams in 2011.


Simple Question : A university chemistry team has synthesized a new phosphate in 2011 with this formula : KCuFe(PO4)2


If the charge on copper ion in this compound is +2, what is the oxidation number of iron ion in this compound?

(I found this journal in NUS library! A lot of gems in NUS, NTU and even National Library!)


Physical Chemistry:
Ease of overlap of 2p vs 3p orbitals to form pi bonds 
(eg. N2 vs P4, CO2 vs SiO2)

Effect of percentage s (or p) character on C-C sigma 
bond lengths
pKa of amino acids and how they protonate/deprotonate in acidic/alkaline medium

Unit cells - found in chemical bonding of textbooks. It is out of syllabus but came out in 2011.

Fuel cell – practise prelim papers for novel fuel cells (including hydrogen fuel cells) (Electrochem chapter)

Bond length, delocalisation of electrons in resonance structures , hybridisation

Formal charges in drawing Lewis structures - chemical bonding (came out in 2011 exam papers)

Simple Molecular Orbital Theory in Chemical Bonding

*** Isotopes of hydrogen

Nuclear chemistry – alpha and beta radiation. Out of syllabus but appeared in exam paper. Nuclear reactors in Japan – how iodine-131 is formed. This chapter is found in Peter Cann and Peter Hughes "Chemistry" textbook.

Practical physical experiments – eg. Enthalphy change of reaction, kinetics
Solubility of Group II hydrogencarbonates, carbonates, hydroxides and sulfates. (Inorganic chemistry)

Reverse Osmosis and water treatment


Nernst Equation in Electrochemistry

Inorganic chemistry:
Transition metal – absorption spectrum, colours of transition metal ions and their compounds, eg. Colour of [CuCl4]2- complex. (Cambridge loves this!) Reaction of copper(II) ions with dilute and concentrated hydrochloric acid. Colours and chemistry of manganese, iron, vanadium and chromium compounds. Colours of complexes came out in 2011 exam papers.

Crystal Field theory (strong vs weak field ligands, 
high spin vs low spin complexes)

Practical inorganic experiments – eg. Gravimetry Analysis (Nickel ions with EDTA4- titrations)

Fullerenes, buckminsterfullerene, carbon nanotubes (found in general chemistry textbook), graphene

Simple Nanotechnology (simple knowledge will do)

* Clock reactions in chemical kinetics

Ellingham diagrams in Gibbs Free energy and Entropy (came out in one HCI test)

Phase diagrams

Mass Spectrometry

Enzyme Inhibitors, Enzyme co-factors

Micelles (Bonding and forces of interaction)

***Diagonal relationships (eg. between Beryllium and Aluminium)

Organic Chemistry:

***** Practical organic chemistry – eg. How Reflux process is actually done, separating organic products from their impurities, apparatus for performing organic experiments, how aspirin is manufactured

Grignard Reagent – Organic chemistry. Read up in an organic chemistry textbook

Destruction of ozone by CFC mechanism in the chapter of halogenalkanes

Polymerisation – Organic chemistry. It is out of syllabus but appeared in 2010 exam paper

Reaction of halogenoalkanes with sodium ethoxide (also E1 / E2 versus Sn1 / Sn2 reactions); Williamson Ether synthesis

addition-elimination mechanism for nucleophilic acyl substitutions

Enols & Enolates (iodoform mechanism)

Imines & Enamines (2,4-DNPH mechanism)

Nucleophilic Acyl Substitution (addition-elimination mechanisms involving : esters, amides, acyl halides)

Ethers & Epoxides (mechanisms)

Organic Chemistry Redox reactions (mechanisms for reduction, oxidation states within organic compounds)

Azo-dye formation and diazonium salt formation (mechanism)

******* Arrow pushing in organic chemistry mechanisms

Dienes (resonance and bond lengths)

Acetic anhydrides

Hofmann degradation of amides (Came out in 2011 Exam Papers)

Friedal-Craft alkylation and acylation of benzene (including mechanisms)

Diels-Alder reaction (found in university organic chemistry textbook from your school library)

The differences between reducing agents such as LiAlH4, NaBH4 and hydrogen gas with nickel / palladium / platinum catalysts

Conformation of cyclohexane (found in organic chemistry textbook)

Alkynes and sp hybridisation

Green chemistry

(Cp)2Fe where Cp is cyclopentadiene

Melamine and DEHP -- food scare in Taiwan in mid-2011

2011 P1 Q27 "Nucleophilic acyl substitution of Amines 
unto Amides" (mechanism)

Ylides and the Wittig Reaction (mechanism)

Fries rearrangement (mechanism)

Hofmann rearrangement (mechanism)

Aldol and Claisen condensation reactions (mechanism)

Huckel's rule

** Propofol - the anaesthetic drug that poisoned Michael Jackson to death. A liposuction death of a Managing Director in Singapore was also administered this drug by two doctors. 
Questions may come out in tests or prelim papers this year 2012. Wikipedia for this drug molecule.

Electrophoresis of Amino acids (migration to cathode vs 
anode) based on their Isoelectric points

Biochemistry:

Structures of glucose, sucrose, carbohydrates, DNA, lipids

Haemoglobin (including iron(II) ions in haemoglobin) and chlorophyll

ATP and ADP and their roles in biochemistry - simple knowledge will do

Miscellaneous:
Group IV elements and their chemistry - inorganic carbon chemistry is getting important.
Graphene
Manufacture of sulfuric acid
Semiconductors
Solar cell materials
Ceramics
Free radical organic polymerisation reactions and their mechanisms



Some textbooks to recommend:

You may refer to Bedokfunland JC’s website for some recommended textbooks.

Here are mine:

A-level Chemistry by Ramsden

Chemistry for Advanced Level by Peter Cann and Peter Hughes

University Textbooks :

Organic Chemistry:

Organic Chemistry by John McMurry

General and Physical Chemistry:

Chemistry3 by Burrow, Holman, Parsons, Pilling, Price

Optional : Inorganic Chemistry:

Inorganic Chemistry by Catherine Housecraft and Alan Sharpe
simple_minded aka Mr Chong
Private tutor
ex-MOE teacher
B.Sc(Hons), Dip in Education
E-mail: chemguide7 at hotmail.com
HP : 8 five 9 one 971 zero

http://alevelchemistrysg.blogspot.com


P.S. The more you are exposed to chemistry concepts, the more you understand the paradigm of the scientists. Make chemistry a delight, not a duty or a chore. And you will score well. Be curious! Do not worry, even if you do not read any of these topics, you can still keep cool in exams and solve the problems. You just require more thinking on the spot!

You may use wikipedia to read more about the topics mentioned above.

# Mr Chong is not responsible for any inaccuracies or the topics he highlighted that do / do not appear in assessments. Chemistry knowledge is vast and examiners have a large scope to test for in exam papers.



3 comments:

  1. If I am not wrong, a compound similar to acetic anhydride came out in Paper 3 2012 Papers. I did mention iron compounds in transition metals and it came out in Paper 3 too.

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