In the first few weeks, we used the microscope to look at microscopic object like cells. We looked at onion cells, cheek cells and even blood cells from my classmate Junius who ‘donated’ them! I spotted the nucleus of the cells and saw how the plant cells were arranged. We learnt about the cells’ division of labour and why it happens. Few weeks later, we did a fun experiment including soaking and egg in dilute hydrochloric acid and waiting for 2 weeks. After 1 week, we did not manage to see the results as it was a holiday. On the 2nd week, we found that the egg did not change much. It actually expanded, according to my science teacher, but for the 1st week, it expanded, then for the next, it contracted, so there was not much difference. Also for diffusion and osmosis, we looked at our teacher do the visking tube experiment, which includes water diffusing through the visking tubing, showing how diffusion actually works. As for transfer of thermal energy, we did an experiment including a black and a shiny tin, and how they differ in their heat absorbing and radiating properties. For this topic, we also watched a few YouTube videos on some experiments related to heat and the expansion of matter. We did not do these experiments since it was general knowledge and most of us did it in Primary school. We also discussed and debated on some issues our teacher questioned us on. All in all, term 3 was quite an interesting term with many new things to learn, I have enjoyed this term and hopes that there will be more experiments in future. I love experiments!
Wednesday, September 22, 2010
~Term 3 practicals~
~Term 3~
In term 3, we mainly focused on cells, diffusion and osmosis and transfer of thermal energy. I especially like the stories given out by my teacher, about Alexis St. Martin and so on. These stories demonstrate how people in the past contributed to science through accidents or new discoveries. Cells is a topic where we learn more about how our body systems work, like the functions of blood cells or the digestive system. Osmosis and diffusion were not covered in Primary school so it was a new topic to me. We learnt about why and how diffusion takes place and how osmosis was a special form of diffusion. Then we studied a little on dialysis and how osmosis was involved in it. The last topic we covered was the transfer of thermal energy, also about the expansion and contraction of matter. At last, following this topic is this is the September holidays, a time to relax and catch up with homework!
~Term 2 practicals~
Ah… Term 2 practical lessons are really nice! Brownian motion, the random movement of tiny particles in the air. We saw this right in front of our eyes on the projector. It was a black background with white particles zipping all about randomly around the screen. It was explained that it was colliding into air molecules so it had to keep bouncing around. Another thing was separation techniques. I never dreamt of some of these ways used to purify or distil mixtures. I remember there was an experiment about using filter paper to separate water, sand and some other stuff to produce pure substances separated of each kind. It was quite time-consuming and we failed because our filter paper broke, causing the residue to fall right into the filtrate, hence mixing everything together and forcing us to restart the whole experiment. Luckily we succeeded the following time! Another time was that we had to draw out our plan on how we would separate different substances from a mixture, basically the same thing but not a chance that we would fail, since we did not have to do the experiment. But it required more knowledge since the mixture itself contains more substances than the previous experiment mentioned. Trouble was, we had to present it and I was unfortunately chosen to be the presenter. Finally, after the separation topic, it was sabbaticals, IDS and holidays!
~Term 2~
KMT, separation techniques, solutions and suspensions. That’s what we basically did in term 2. The KMT, Kinetic Molecular Theory, is just about atoms and matter, how they react and what happens to them under certain conditions and temperatures. It is quite easy, as long as you are interested. Well I definitely am! The following topics are not too hard either. My favourite part about the science lessons is when my teacher hands out to us puzzle worksheets. The puzzles definitely need knowledge to be solved. It was quite a fun term, although there were more things to learn and remember than term 1.
~Term 1 practicals~
~Term 1~
In term 1, we learnt about some science equipments and various items used in a laboratory. I had my first try lighting a Bunsen burner and using it to heat up stuff. We also learnt about the uses of different equipments like the burette and the pipette etc. I have never come across this in Primary school it was interesting! Afterwards, we learnt how to use the micrometer screw gauge and vernier calipers to measure things too small to be measured accurately by an ordinary ruler. I never knew that these things exist, until the lesson. How I wish I had those stuff back at my house! My teacher sometimes gives to us interesting story handouts about people in the past and how they experimented or achieved in science, for example, the Tale Of The Other Dog. All in all, term 1 was very interesting and is an introduction of future science lessons, probably about more experiments and why they happen.