2010-01-29

Kinetic Theory of Matter

   That's basic chemistry. But when I looked at my students' work in explaining kinetic theory of matter, thousands of questions popped up in my mind. How much do my students understand Kinetic Theory of Matter? It seems that it's such an abstract concept for them.  If I'm not mistaken, a student is exposed to this theory when they were studying Form 1 Science.

  Kinetic Theory of Matter explains that matter consists of tiny and discrete particles, which are always moving.
 
  Perhaps the theory is quite microscopic. We cannot feel it, see it or imagine it. But, there were some phenomena which can prove the Kinetic Theoryf of Matter. For example,
  • Brownian movement.
  • Diffusion in solid, liquid and gas.
  • Changing of state of matter when heat is absorbed/released
  I'll post more how above examples can prove the Kinetic Theory of Matter.

2010-01-17



When you sow an action, you reap a habit;
When you sow a habit, you reap a character;
When you sow a character, you reap a destiny.

2010-01-09

A Perfect Graph


In the beginning of Chapter 1, Rate of Reaction in Form 5 Chemistry, a students needs to draw a graph to show the changes of quantity of reactants/products over a period time.

A perfect graph must have few criteria as follows:


  1. Title
  2. Label the two axes with the correct unit
  3. Choose a suitable scale. The size of the graph should be at least ¾ of the size of the graph paper.
  4. Plot all the points correctly
  5. Smooth graph (curve or straight line )

   Most of the time, I found my students a bit hard to draw a perfect graph especially when drawing a smooth graph.  Perhaps they need a sharp pencil and more practice.  The skill again will be assessed in PEKA through the coming experiments to investigate the effect of temperate and concentration of reactants on the rate of reaction. All the best and good luck!!

2010-01-01

Are Food Additives Good???

Food additives are added in a small quantitiy in food, mainly to
  • make the food last longer
  • add flavour
  • enhance the food colour
  • improve the food texture
There many types of food additives, as follows:

Do all these food additives bring any harm to our health? It's a question to ponder.
For example, if food which is rich with salt might cause high blood pressure, heart attack and stroke. High intake of sugar cause diabetes, tooth decay and obesity. Some other food additives, as we explore more through this folio, we will realise their disadvantages.

Do our family members like to add lots of MSG into their mee? Does our little brother like to eat a lot of colourful sugar? Try to think few of your family member eating habits and advice them after you realise some disadvantages of food addtivies.