November 15, 2012 — chemistry, classroom
Chemical equilibrium, denotes a reaction condition established when it’s a:
- Closed system
- Reversible reaction
- Dynamic (no visible change, but reaction happens in microscopic level)
- Rate of forward reaction = backward reaction (rate of forming products = rate of product dissociation)
You have searched for most common equilibrium processes last week. The ones you must really nail are these two processes:
- Haber-Bosch‘s ammonia synthesis
- Contact process of manufacturing sulfuric acid (why is it named ‘contact process’?)
The above processes are not all consist of equilibrium reactions. Only ONE reaction for each process. Make a note of which reactions they are and the condition (pressure, temperature, catalyst). (psstt… these are usually the conditions asked in your test).
The conditions stated for the manufacture are the optimised ones. Means they may not give the most abundant product, but they are a good trade-off between good yield and cost of process. Very high pressure may give the most gas product yield, but it will be very expensive on maintaining the pressure and more dangerous for the plant’s workers.
Optimisation, or getting the most suitable compromise, works by shifting the equilibrium. Just like when you’re climbing on an escalator that’s moving down. In order to stay in a certain height, you must climb with the same speed as the escalator, but in the opposite direction. And when you want to go to a new height and stay there, you must climb faster first. Then, when you have reached the new height, you will have the same speed as the escalator again.
This works the same with equilibrium reaction. When equilibrium state is reached, the reaction is dynamically stable. Means, it can change. By changing pressure and/or temperature, you can set the reaction to a new equilibrium. The reaction will then move faster toward forward (or backward) position, then stays there in the new equilibrium state. This change of equilibrium state is what we call EQUILIBRIUM SHIFT.
Equilibrium shift works on Le Chatelier’s principle (he’s a French, so make sure you pronounce it right). Make note on what will change equilibrium position (factors affecting equilibrium) and what the effects are. [if you have done this in your last week's task in library, it will not be something new for you]. “What will happen if you raise the temperature, will you get more or less product?”, for example.
There could be specific terms on when the factors are NOT applicable. For instance, you can’t shift the equilibrium position of reaction if all the reactants are solid.
Your task would be working on the ‘Latihan 4.2′ in your Kimia 2A Erlangga book. To make working on it easier, understanding the ‘Uji Kepahaman’ questions 4-15 will help. Should there be any difficulty, you can ask here or you can always mention me in Twitter through @litachem.
Tweet you later, kids!
Here are worth websites to visit on equilibria (don’t say I didn’t tell you):
July 16, 2012 — classroom
Dear fresh brains of XI and XII grades of SMA 8 Jakarta, I welcome you to my chemistry class *grin*. A different level could disarm everything you have known, as if you didn’t learn anything relevant last year. Worry not. It’s just a symptoms of holiday. Or so we hope, for your good sake.
Here is my take on how we supposed to learn: using our brain, in terms of utilizing our gift, SENSE. You might feel uneasy when I pushed you with questions that you didn’t care what the answer is, moreover you think important for your life. Guess what, you may not get ANYTHING useful for your life during high school, IF you resist to learn using your mind. Drown in misery of uselessness you may say later.
But I should remind you this: learning is YOURS. Learning is not listening, or doing homework, or memorizing formulas, or quick calculations. Learning is what you get and use in your life, after you depart from school gate. Could be the very day, or years after. It’s how you take & deliver things, not only the subjects themselves.
So whether you learn something or not, it’s your choice. I choose to take chemistry into my life & use it on daily basis to make choices. What’s yours?
February 18, 2012 — Uncategorized
You may find these files helpful for you. I downloaded them from the internet. So the right’s keeper is their creator. Any permission should be addressed to them. Please bear in mind, for nomenclature, this could be different from our National Curriculum. Be aware of what’s expected from you in your current curriculum.
A2-Organic reactions spider diagram
Rules on Drawing Structures
Nomenclature & Isomerism
July 10, 2010 — Uncategorized
Syllabus, of course.
This will be the guide of your A-level course. Targets which should be completed, what’s what (define, describe, explain, suggest), details, changes from previous syllabus, and at the end of the syllabus: Data Booklet. You need to get used to this one since this is the helpful tool for you instead of writing tool and calculator.
If you’re XII graders, you will still be using 9701_y10. If you’re XI graders, you will use 9701_y11. Download it here.
What? Study guide? Well, no, I don’t use it. There’s revision checklist for you to check your progress. Download it here.
A-level Science Applications Support Booklet
This booklet talks about applied chemistry and a bit about biochemistry. All A-level (A2) Chemistry candidates MUST have and study this one as a starter for your exam preparation. Good for others as advanced knowledge, too. Download it here.
July 10, 2010 — classroom
Here are the name list of XII-Science students. Sorry I only took the science class list home. You can see all the list (for XI graders, too) on the announcement board at school.
Homeroom teacher: Lita Mariana
- Alex Beny K. –> chairman
- Alysha Athia
- Arief Dimas Dwiputro
- Cindy Dessidia Gamal
- Danaparamita Hapsari –> secretary
- Dimas Wahyu B.
- Dina Rahmatika
- Dini Mardhiyani
- Diva Magistee
- Dwinia Emil
- Khalda Az-Zahra
- Nadilla Fedriany Soenardhi
- Nisrina Nur Amalina
- Pramesti Istiandari
- Ryan Adriansyah
- Ryandanu Priwanta
- Soefiannagoya Soedarman
- Widya Hayu Lestari
Homeroom teacher: Yustrida Maisa
- Aninda Fariza
- Aulia Rahman Anshary
- Centane Onanda Nasri
- Dinda Larastika Riyanto
- Dyah Astri Paramaramya
- Eleny Marsha Claudia
- Ephraim Deviaro G.
- Evellyna Meilany
- Hakim Cahyodewanto
- Karina Dhaniarti
- Muhammad Irfan Perdana
- Naufal Elang Ciptadi
- Navintya Cesvini
- Putri Widya Utami
- Rifina Ramdhiantri Rahisa
- Zara Juliana
Homeroom teacher: Dewiyanti
- Alifia Nuril Ikrami
- Allinka Ilmarani
- Emir Hanniverano S.
- Ghaisani Shabrina R.
- Gregorius Bramantyo A.
- Lintang Tunjung Manik
- Nadia Hanani
- Reza Fadli Rizkianto
Guidance & Counseling teachers
XII Science A & B: Priadi Tri Handoko
XII Humanity: Sri Hartatik