Handphone confiscation

I confiscated 2 handphones in class last night. Unless u prove to me u have 4 brains and can absorb what is electrolysis and its application while replying likes and texts on ig/WhatsApp. Next time any student who texts in class will not just get their handphone confiscated but do a TikTok on Mr Lim’s channel to bohemian rhapsody. I will get u that 2 million views if u want.

Happy Chinese New Year!

When u talked about 守岁 (keeping awake for well wishes for your parents for the new year) in your classes on new year eve with Mr Lim and all classes including RI class’ chinese cannot make it. It’s not 守睡。 thanks NYGH class for rectifying that it’s 守岁。 and definitely not 守夜! (keeping vigil at a funeral wake)


Thank you for all the well wishes. It is really rare for a tuition teacher to receive cards and gifts for Teacher’s Day and i appreciate these as testimonials, and I am just very grateful that you enjoy my lessons and are motivated to excel in the subject.

Teacher’s Day 2019 Well wishes

Happy Teachers’ Day! 

Thank you for teaching me chem for the past 1 year. I genuinely would not have passed chem without all your booklets and notes! The chem bible is really my bible before exams 🙂 I’m really grateful that you reply to all our whatsapp messages so fast and prepare all the very useful worksheets and questions for all of us, these really help.

Happy Teachers’ Day!  


Dear Mr Lim, thank you for being such a dedicated and caring teacher. Even though you are a tuition teacher, you have never failed to go the extra mile to be of the best help you can for each and every one of your students, working much harder than some of my school teachers! XD Your unwavering support and endless dedication never fail to inspire students. It is because of you believing in us that gives us the inner drive to press on to succeed. 


                                                                                                              ~Clifford Oh~

                                                                                                                6  .  9  .  19 

Dear Mr Lim, 

Happy Teacher’s Day!

Thank you for all the hard work and effort you have put into teaching us this year, from tirelessly sourcing for and compiling questions for us to practice, to answering any questions we have patiently! Thank you for making lessons engaging and easier to comprehend, and I have really enjoyed your Chemistry lessons!

                                                                                                                      ~ Tanya 🙂 


Dear Mr Lim,

Thank you for teaching me Chemistry since last year! I used to fail Chemistry in Sec 3 but now it’s one of my favourite subjects, thank you very much for helping me. I’m very grateful I started going for your classes, it really changed how I view the subject. I hope these teacher’s day clips make the teaching life easier!

                                                                                                                     ~ Eva 

Dear Mr Lim, 

Thank you for being an inspiring and interesting teacher! You’re chem god in all our hearts. I used to dislike Chem immensely before I joined this tuition but now I’ve improved so much because of your guidance and encouragement 🙂 your encouragement makes me want to work harder! 


                                                                                                                     ❤️Janelle Teng 

Dear Mr Lim, 


Thank you for the constant guidance and help you have given me in the past two years. I’m very grateful for all your encouragements along the way. Really appreciate the time and effort you put in to help improve our chemistry and I enjoy your lesson a lot!! 

                                                                                                              ~Crystal Chen

                                                                                                              06 . 09 . 2019

Dear Mr Lim, 

                                                 Happy Teacher’s Day 

I’m really grateful for your guidance & patience + thanks for making lessons so much more interesting. Thank you for everything! 

May God bless you loads 

                                                                                                                    ~ Annabelle 

Mr Lim, 

Thank you so much for your guidance in Chem so far! My understanding has greatly improved and I’m very thankful for you! May God bless you and grant you the desires of your heart! May He be with you in the year of the Latter rain! 

Happy Teacher’s Day!! 🙂


Dear Mr Lim! 

Thank you for being a very patient and dedicated chem tutor. Through your lessons I am able to understand chem better and have even started to appreciate the subject! Also, I appreciate that you always take time to explain the concepts that I don’t understand and that you always encourage us to ask questions no matter how ridiculous or small they may be. I promise to work hard this year for chem O levels and I am glad to have an amazing chem tutor like you to support me through this journey. Furthermore all the best for your future endeavours!


Happy Teacher’s Day Mr Lim! 

Thanks for teaching me Mr Lim. I have never seen a teacher that is so multi-talented before; you’re good in almost everything; chinese, math, science, being buff as fish and good at dancing. 🙂

                                                                                                               ~Darwin Ho

Dear Mr Lim, Happy Teachers’ Day! Thank you for always being so patient and understanding and always going the extra mile for us :”-) Your dedication really motivates us to work even harder for chem. I hope you have a good break after OTAS!


Dear Mr Lim, Happy Teacher’s Day! I am very grateful to you teaching me for the past 2 year. You have made me enjoy chemistry a lot and it is one of the subjects that I have the most interest in. I know you spent a lot of effort making and compiling all the booklets for us and I am very grateful as it is extremely helpful for us. The chem bible was very well done too and it helped me a lot. I just want to say please don’t overwork yourself and rest occasionally ok. I appreciate your effort conducting all the classes for us, and don’t stress yourself too much. Thank you for teaching throughout the past 2 years and I will study hard to repay your effort.

Soong Leng 2019

Dear Mr Lim, thank you for being the most dedicated tuition teacher I have ever encountered in my life (not kidding)! You are really crazy about chem, and your passion for teaching is really infectious. I don’t think I will ever be able to find any chem teacher who would have a chem bible or infinity moles?!?! You are super good at teaching and my grades really rocked after joining your tuition.

Apart from academics, I find it really cool that you post stories related to chem everywhere you go (in Japan’s beer factory or changing gas tank HAHA), it really shows me that what I am learning in sch has a real life application to the outside world! Thank you for answering all my whatsapp questions, being free for a f2f consultation (and even wanting to pay for our meals) and for sacrificing your gym time for our skype lessons. You are so “wei da” it really inspires me to be someone, as capable and dedicated as you in future.

It’s honestly crazy how you can juggle so many things on your plate (and I think I will never understand how), but I am so grateful that you are teaching JC next year! Please rest more and have a very great teachers’ day! God bless!

Nicole Lim – 2019

Dear Mr Lim, Happy Teacher’s Day! I know that teachers never have an easy life too. You have been a great teacher, trying to encourage us to clarify our doubts we have. You spent time giving lectures on whatsapp too. Best of all, you conduct skype lessons! (In around feb apr)(most of the time) I would like to thank you, for giving me the courage to understand and combat chemistry in a better way. Chemistry will never be more interesting without you. Side note: I might need a little more help in organic chem, and my O-level target is more of a B3, if possible A2.

Happy Teacher’s day Mr Lim!

To show my appreciation for you, here’s a little gift for you and since you said you’re in need of red pens, here it is hahaha. Anyways, thankyou so much for constantly giving love and concern to your students and always clearing our doubts online whether you’re busy or not. Your commitment in teaching really inspires me more to work harder for o’s and you’re the first teacher I’ve met that expresses so much joy in teaching. Although our class don’t really or is shy to laugh at your jokes, I hope you know that I really do appreciate your jokes to brighten up the mood! Also, I have been accepted into SP’s Food Science & Technology course! I will continue to improve on my chemistry so that I’ll excel in my upcoming further studies in poly as well. Once again, thank you for being such a bubbly and hardworking teacher! HAPPY TEACHERS’ DAY!!!


Cassandra (Saturday 8am class)

Dear Mr Lim,

Thank you so much for all the effort you have put into teaching us chemistry. I appreciate the time you take to produce all the booklets and the kahoot games which have made be understand this subject better. Furthermore, I am grateful for your patience when answering my questions and caring for our well-being through your many kind actions like the time you extended class by ½ hour just to answer our questions or the time you bought us McDonalds. Regardless of whatever results I may get for chemistry, I will never forget your guidance and support. Honestly, I hope I can do you proud for the time and dedication you have invested in us 😊


Hey Mr Lim,

Thanks for being such an enthusiastic and caring teacher, always there to clarify my doubts and help with problems. You are one of the rare few teachers I have that actually care about us and our performance, so I sincerely want to thank you for everything you have done for me. 😊



The O level Plus Chemistry Program is catered to help both O level and IP students ace their examinations. Syllabus has a two-pronged approach: foundational concepts, and chemical applications in the world to apply concepts and develop strong critical thinking for chemical solutions, targeting data-based questions.

Seb Academy Lessons Updated: 26 Oct 2019

2020 Sec 3 ‘O’ Level Plus ChemistrySchedulesLocked-In Fees
(for every four 2-hour lessons)
$320 (if you register after May)
Tue4.00pm – 6.00pm
Thu4.00pm – 6.00pm
Bukit Timah
Sat2.45pm – 4.45pmBishan
Sun10.30am – 12.30pm
Sun4.15am – 6.15am
Bukit Timah (Hwa Chong IP)

2020 Sec 4 ‘O’ Level Plus ChemistrySchedulesLocked-In Fees
(for every four 2-hour lessons)
$340 (if you register after May)
Tue7.15pm – 9.15pm
Thu7.15pm – 9.15pmBukit Timah
Fri7.30pm – 9.30pmBishan
Sat8.00am – 10.00am
Sat12.30pm – 2.30pm
(suitable for RGS IP /SNGS IP
Sat5.00pm – 7.00pm
Sun8.00am – 10.00am
Bishan IP (RI/RGS IP)
Sun2.00pm – 4.00pm
Bukit Timah (Nanyang Girls Sec 4 IP)
Bishan505B Bishan Street 11, #01-422,Singapore 5725053-min sheltered walk from Bishan MRT Exit A
Bukit TimahBukit Timah Shopping Centre, 170 Upper Bukit Timah Road, #05-04, Singapore 588179Next to Beauty World MRT


Mr Sebastian Lim specialises in coaching students for a focused, accelerated path to ace their first major papers at the O levels and Year 4 IP program. His vivacious teaching style and strong academic background from Hwa Chong and NUS has made him a popular and effective teacher amongst his students. With 5 years of teaching experience under his belt, his insightful lessons and exam prep tips have propelled students towards excelling at the examinations. Mr Lim enjoys mentoring young individuals to develop their full potential in secondary and tertiary education. He was the winning mentor to a team of students from Hwa Chong Institution college section for the Best Business Idea competition for entrepreneurship and start-ups in 2013. He actively seeks a mentoring role to his students in both academic rigor, which include school projects, competitions and holistic education from his past academic success and experiences. Mr Lim had represented Singapore to successful win the South-East Asian round of Henkel Innovation Challenge in 2012, a competition to present innovative ideas and market solutions to the world. He actively seeks to inspire students towards excelling in their education and academic projects with a competitive streak.

Bleaches and 2019 O level Chemistry Paper 2 Database Question

Bleaches were the focus for the 2019 O level Chemistry Paper 2 Database question.

Bleach is a necessity that is used daily, to remove colour pigmentations and to sterilise unhygienic areas. It is used to whiten wood pulp to make tissue papers or the paper we use to write on, and in flour for making bread. 

Bleaching works by releasing oxygen molecules in a process (oxidation). The released oxygen molecules break up the chemical bonds of chromophores and reflect either no colour or a colour outside of the visible spectrum.  The active ingredient in Clorox household bleach is sodium hypochlorite (NaOCl), which performs the bleaching, stain removal and disinfecting functions. Other chemical ingredients in Clorox include sodium chloride (salt), which thickens and stabilizes the solution.

Although household bleach is not corrosive or toxic, bleach exposure can cause irritation in the eyes, mouth, lungs and skin. Not only is bleach harmful on its own, but its interactions with other commonly used chemicals can produce harmful reactions. When bleach comes in contact with ammonia, it can react to form chlorine gas, which causes cellular damage in the nasal passageways and lungs. The accidental mixture of these two products in homes has resulted in death.

In addition, chlorine gas can also form when bleach NaOCl reacts with acids, such as vinegar. Bleach is especially damaging to the environment because it lingers for many years. Even small amounts of the toxic chemical can accumulate in air and water over time, which can eventually result in adverse health effects. In the O level Chemistry Paper, besides NaOCl, another bleach of consideration was hydrogen peroxide.

Image result for what is bleach
a picture of some household bleaches
Image result for what is bleach
This is chlorox, commonly used at home for bleaching your clothes’ stains.

Seb Academy Grad Night

There will also be a non-compulsory seb academy grad night for the students to celebrate their end of o levels and exams at: Urban Tavern Bugis

2A Pahang St, Singapore 198604
9388 0166


Date: 16/11 sat 6.30-9.30pm.

I’ll be booking the venue for all Sec 4 students to come together with their classmates to celebrate a little achievement for completing their first major exam. The cost is $10 and buffet dinner would be catered. There would be some games and also I’ll do a little sharing of post-exam tertiary education stories so they can have a little expectation of what post o level and Sec 4 would mean for them. Please let me know if you would be interested in attending by 11/11 so I can cater for the food.

you can go to the website of: https://urbantavern.sg to view what we have for your graduation night. There is a pool table, karaoke, darts, and of course, food, for you, and your classmates to enjoy after a year of hard work, going through many interesting and in-dept questions with me in preparing for your sec 4 ip exams or o level exams. I am most proud of you for what you have done and i hope you can come to celebrate a night of achieving this feat together.

2019 Seb Academy Raffles results

2019 Seb Academy Raffles Results for Sec 4 Raffles students: GPA 3.9/4.0 an improvement of 0.1 from 2018!

2018 Seb Academy Raffles Results for Sec 4 Raffles students: GPA 3.8/4.0

  • students from 2019 Raffles Institution and Raffles Girls’ Secondary School cohort