More details, please read http://www.mysinchew.com/node/58773
Quick tip when giving inference. Ask yourself WHAT, HOW, WHY.
How does this solution formed? White powder reacts with//dissolve in water.
Why does this solution turns red litmus paper to blue? The solution is alkaline.
What is that solution? It is potassium hydroxide.
Inference: Potassium oxide reacts with water produce potassium hydroxide which is an alkaline solution
- Combustion of metal in oxygen
- Reaction between metal oxide and carbon
- Reaction between metal oxide and hydrogen
- Conversion of Fe2+ ion to Fe3+ and vice versa
- Displacement of metal from their salt solution
- Displacement of halogen
- Transfer of electron at a distance
- Rusting of iron
- Electrolysis of aqueous solution & molten compound
- Chemical cells
- oxidized substance and reduced substance
- oxidizing agent and reducing agent all all those reactions
- gain/loss of electrons
- change in oxidation number
Thanks to Mr Yeoh for published this analysis through his blog http://spmchem.blogspot.com/
So far questions from the following states are uploaded:
SBP 2011: Paper1_Paper2_Paper3_Answer
Kedah 2011: Paper1_Paper2_Paper3_Answer
Terengganu 2011: Paper1_Paper2_Paper3_Answer
Negeri Sembilan 2011: Paper1_Paper2_Paper3_Answer
Johor 2011: Paper1_Paper2_Paper3_Answer
Perak 2011: Paper1_Paper2_Paper3_Answer
Melaka 2011: Paper1_Paper2_Paper3_Answer
Sarawak 2011: Paper1_Paper2_Paper3_Answer
Pahang 2011: Paper1_Paper2_Paper3_Answer
Perlis 2011: Paper1_Paper2_Paper3_Answer
Kelantan 2011: Paper1_Paper2_Paper3_Answer
Penang 2011: Paper1_Paper2_Paper3_Answer
|The self inflate ballon attracts small kids' attention during K2M 2011|
- Add 1 table spoon of baking powder to a ballon with a funnel.
- Fill a bottle with halfull of vinegar.
- Attach the ballon with the baking powder to the bottle.
- Quickly por baking powder from ballon the bottle.
When the baking powder(sodium bicarbonate) is mixed with vinegar(ethanoic acid), the reaction produce carbon dioxide, water and salt. The production of carbon dioxide gas inflate the ballon
- keep ice cream frozen
- as a refregerants in pharmaceutical, blood and organ shipment
|When dry ice sublimates in the glove, the carbon dioxide gas released filled up the glove.|
|My students during K2M 2011 at National Science Centre|
|Latex coagulates when acid is added.|
- Latex is a mixture of rubber particles and water. Rubber particle is made up of a protein membrane that surrounds many rubber molecules.
- The negatively charged protein membrane prevent repel each other. Latex does not coagulate.
- Acid which consists of H+ ion is added into the latex.
- The H+ ion from acids neutralize the negatively charged protein membrane.
- The rubber particles collide with each other.
- Protein membrane of the rubber particle breaks.
- Rubber molecules clump together. Latex coagulates.
- Bacteria from the air enter the latex.
- The growth of bacteria produces lactic acid.
- Lactic acid causes coagulation of latex. But this process occurs slowly. Why?
- Slow bacteria action.
- By adding ammonia solution.
- Ammonia solution consists of OH- ion that neutralize the acid produced by the bacteria.
- The rubber particles remain negatively charged.
- Coagulation of latex is prevented.
|5H students are studying coagulation of latex by adding ethanoic acid|
|Ethanoic acid is added drop by drop into latex in the beaker. The latex is stirred by using glass rod.|
- Magnesium is more electropositive than copper. Magnesium is the negative terminal.
- Each magnesium atom donates two electrons to form a magnesium ion. Mg --> Mg2+ + 2e-
- The flow of electrons from the magnesium ribbon to the copper through the external circuit results in the production of electricity.
- The hydrogen ions from the electrolyte(sodium chloride solution) are discharged at the copper plate by accepting electrons to form hydrogen gas. 2H+ + 2e- --> H2
- Heat of neutralization between a strong acid and a strong alkali is always -57.3 kJ mol-1. Why?
2. Heat of neutralization for neutralization involving weak acid or weak alkali is less than -57.3 kJ mol-1. Why?
Weak acid/akali does not ionises completely in water. Some energy released during formation of water is used to ionises the weak alkali/acid.
Energy change when one mole of water is formed from the neutralization between one mole of hydrogen ion from an acid and one mole of hydroxide ions from an alkali.
|5H students are carrying out experiment to determine heat of neutralisation between an acid with an alkali.|
All the best to all Chemistry SPM candidates from SMK Puchong Jaya.
|Polypropylene as fabric|
- The first polypropylene was produced by Professor Giulio Natta in 1954.
- It was later widely used as injection moulding applications(Example: packaging, parts for electronic and electrical appliances, caps and closures, toys, luggage and a variety of household goods)
- Second largest use iof polypropylene is n fibres sector. (Example: thermal underwear & storage box)
- Film & sheet market: uses in the pacckaging of sweets, snack foods and cigarettes.
- The structure of polypropylene(polypropene)
|Isomers of butene|
- position of carbon-carbon double bond
Their names are as follows:
General formula of Carboxylic acids: CnH2n+1COOH, n = 0, 1, 2.....
All the carboxylic acids have the same functional group, which is carboxyl group, -CO
Can you write molecular formulae and draw structural formulae for the molecules in the album above?
Feel free to drop your answers in the comment box.
In commerating International Year of Chemistry 2011, school has planned a series of activies as follows:
1. Essay Writing Competition(EWC)
Theme: Chemistry – Our Life, Our Future
*limited to 3000 words only. For more details, click here.
Open to all students. Essay of the winners will be submitted by the Principal of the school for the National level EWC. Grand prize is waiting as the first prize winner in the national level will be fully sponsored to attend the closing ceremony of International Year of Chemistry in Brussels, Belgium from 1 - 3 Dec 2011.
2. Atomic Structure Design
Use your own imagination and contruct your own 3D atomic model. You're free to use any materials.
3. My Periodic Table!
What is your own version of Periodic Table of Element! Prepare one and share with us. The creative one will be the winner!
4. Chemistry Quiz
Date: 11 April 2011
Topic: Numerical Problems relating the concept of moles, chemical equation & concentration.
4 students will be chosen randomly from each form 5 on the day of event to take part of the quiz. The more question you answer correctly, the nearer you are to the grand prize!
5. Karnival Kimia Malaysia(K2M) 2011
Date: 15 April 2011
A bus of 40 students from our school will attend K2M which will be held in National Science Centre. A series of activities is waiting us : poster exhibition, demonstration and hands-on experiments, slide and video shows, talks & lectures on the theme and sub-themes, quiz and competition, etc.
In conjunction with International Year of Chemistry 2011(IYC), Malaysian Institute of Chemistry will organize a series of activity to promote awareness of public towards the importance of chemistry.
Event planned for students are
- Karnival Kimia 2011(K2M 2011) which will be launched on 15 April 2011 at National Science Centre.
- IYC Essay Writing Competitition for Upper Secondary School Students.
For more details, please visit Malaysian Institute of Chemistry official website.
Date : 21 July 2011(Thurday)
Time : 10.00 am.
Registration fee: RM10
Students who perform excellent in this quiz will be shortlisted for getting ready for International Chemistry Olympiad(IChO). For more details, click here.
Any students who are interested, please register with your chemistry teacher. Closing date is 27 May 2011
Who can take part?
Students all over the world(12-14, 15-18, undergraduates/teacher students)
design a national stamp that reflects on 'Chemistry as a Cultural Enterprise', showing the chemical impact on
the culture and/or every day life in your country.
Start of the Competition
29 Jan 2011
End of the Competition
15 June 2011
Winning Design will be on show during the IYC 2011 Closing Ceremony in Belgium on 1 Dec 2011.
For more details, click here.
Many students always get confused when using the dilution method formula especially when susbstituting value for V1.
For the above situation, we shall substitute the value as follows.
M1V1 = M2V2
2V1 = 0.2(100)
V1= 10 cm3
From the calculation, we know that
- 10 cm3 of is pipetted from 2.0 mol dm-3 sodium hydroxide solutoin and transferred into a volumetric flask.
- 90 cm3 of distilled water is added into the volumetric flask. The volumetric flask is shaken well.
- 100 cm3 of 0.2 mol dm-3 sodium hydroxide solution is ready.
- Proton number of sodium is 11.
- Nucleon number of sodium is 23.
- Sodium atom has 12 neutrons.
- Sodium atom has 11 protons.
- Protons and neutrons are found in the nucleus of the sodium atom.
- Sodium atom has 11 electrons. The electrons are moving around the nucleus in their shells.
- Electron arrangement of sodium atom is 2.8.1.
- Sodium atom has 1 valence electrons.
Thanks Mr Adura from ASIS.
Actually, the question is quite direct. There are many possible experiment plan. In fact, in student's textbook, students were asked to plan an experiment to study whether copper (II) sulphate affect the rate of reaction between zinc and sulphuric acid too.
Some useful guides when attempting this question:
- Give an example of acid & metal.
- How does metal react with acid? What is produced?
- How to do measure rate of reaction in an experiment? Hint: Rate of reaction is measured based on observable changes of quantity of reactant/product over a period of time.
- What are the required information/data to compare the effect of catalyst on the rate of reaction?
- Try to imagine the materials & apparatus required.
- Draw diagram to show the set-up of apparatus for the experiment.
- Think of the steps to set-up the apparatus till recording data required.
- Write down your plan.
- Recheck your plan. Especially for materials, apparatus & procedure & tabulation of data. Students do forget some important point.
Some molecular models of few members of alkanes. Can you name them?
|5H students were happilly showing their molecular models after constructing few models of alkane members.|
|5C students are calculating number of atoms present in an alkane molecule.|
|Students are constructing the molecular model of decane in groups.|
|A student proudly showed her completed handout after using the molecular model of alkane.|
Recently a bus of teachers & students from Jawa Tengah visited my school. Initially, the visitors were planned to observe my chemistry class with 5H. But it went out not as planned. Few teachers & students dropped by my chemistry class and stayed with us for a while. At that moment, I was showing a video relating reaction between hydrogen & iodine. The girls were asked to explain the requirement for a chemical reaction. Luckily the lesson went well as planned.
- J.J. Thomson discovered electron.
- Ernest Rutherford discovered the proton
- James Chadwick discovered the neutron.
In your opinion, how does an atom look like? How about a carbon atom?
Please respond by leaving your comments & names.
Before the experiment, they were ready with their experiment plan. Most of them were able to write a satisfactory experiment plan. However, the aim of the experiment, problem statement were not specific. Some even were not ready with their table. Hopefully they would improve after discussing with me.
The students were able to carry out the experiment with correct technique & skills. Well done, 5C students!
|The student was taking time for mark 'X' dissapear from view.|
|Cooperation is shown througout the experiment.|
|The conical flask is swirled once sulphuric acid is added into sodium thiosulphate.|
|Mark 'X' is observed from top of the conical flask. The other pair of students were discussing their data.|
Chemistry SPM was on 6 Dec 2010, which is a week ago. As I go through the question paper in more details, the arrangement of the question was slightly different compared to the last few years. Normally questions involving calculation or more difficult question are arranged at later part. But this year the questions are seems more likely arranged according to topics in chemistry syllabus.
No of Question
|2 Structure of atom|| |
|3 Chemical Formulae & Equations|| |
|4 Periodic Table of Elements|| |
|5 Chemical Bonds|| |
|6 Electrochemistry|| |
|7 Acid & Bases|| |
|8 Salts|| |
|9 Manufacture Substances in Industry|| |
|1 Rate of Reaction|| |
|2 Carbon Compounds|| |
|3 Redox|| |
|4 Thermochemistry|| |
|5 Chemicals for Consumer|| |
For answer for this paper, please click here.