Students' Definition of Rate of Reaction

In one of the question in the recent examination, one question asked about the meaning of the rate of reaction. I compiled the answers from one of my class. The following are their answers:  

  1. Change amount of reactant or product against time
  2. Change in the amount of reactants against product formed
  3. Change of selective quantity of product or reactant against time
  4. How fast the reaction occur at particular time
  5. How fast reaction takes place in a reaction
  6. Measurement of the amount of change of reactant or products against time taken
  7. Rate of formation of product over time
  8. Rate of substance to react with solution
  9. Speed of a chemical reaction
  10. Speed of reaction of a substance in one second
  11. Amount of reactant that has been used up or the product that is formed in a unit of time
  12. The amount of product produced in a reaction to time
  13. The amount of products formed in a reaction per time
  14. The amount of reactant over a time
  15. The amount of reactant used up or the amount of product obtained per unit time
  16. The measurement of the change in amount of reactant or product against time
  17. The rate of change of reactant or product over time
  18. The rate of time that a substance is able to react completely with another substance
  19. The time taken for a reactant to react completely
  20. The time taken for the reaction occur
  21. Time for reactant to react to produce product
  22. Time or the speed of reaction to take place
  23. Time taken for the amount of reactant react to produce an amount of product
  24. Time taken for the reactant to be reacted
  25. Time taken needed for the volume to undergo chemical changes

NONE of them gave the same answers. Each of them has different understanding of the definition of Rate of Reaction.  But most of them have misunderstood the term! Only answer 3 give an accurate definition.  What a pity! Perhaps some of them did try to memorize during revision, but memorizing without understanding is not effective at all.
Let's have a look, what can I do to clarify this when I enter their class later.


Pertandingan Poster Minggu Sains & Teknologi 2010

Johan: Tan Ying Li, Tan Yi Han, Pavittrah a/p Mohanan

Naib Johan : Nurul Huda bt Azhar, Nursharina bt Mohd Yusof, Kharun niza Waznah bt Baharin

I received many entries from students during Minggu Sains & Teknologi 2010. To my surprise, my students are not only good in their chemistry concepts, they have talents to in arts too! Keep up the good job!


Saturated fat molecule or unsaturated fat molecule

Molecule A

Molecule B

Based on the structure for both fat molecules,
  1. Which molecule is a unsaturated fat molecule? Why?
  2. Which homologous series does molecule A belong to? Why?
  3. State two difference of both molecules.
  4. Which molecule can undergo catalytic hydrogenation? State the condition of the reaction.


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This is one of the question in SPM 2006 Paper 3. The following photo might help to give you a hint to write the experiment plan.

For suggested answer, please click here.


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I found this document from Scribd posted by khayranizam.  It is useful for revision as the notes are compiled in the form of mind map.

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