Science Practicals

One aspect about Science lessons which makes learning more interesting would be the practicals carried out roughly once a week. Such practicals allow us to see the reaction between acid and carbonate for example, in front of our eyes rather than just a statement on the notes. Does it enhance our understanding of the reaction? It does to a large extent, having seen it happen before our eyes.

However, we would forget what was learnt during the practical few days after the practical itself. Then when it was time to study for tests, we would re-visit our notes and start refreshing our memory. My point is that practicals serve more as a tool of engagement and interest rather than pure understanding and memorizing it for a long time. Often what we learn from the practical only last in our heads for a day.

Practicals are not entirely useless though. On the bright side, we can say that carrying out practicals improve our lab technique which will be tested somewhere in the near future. Lab technique, in my opinion, is very important not only because it will be tested, but it will be beneficial for those who choose Cat-1 for their Project's Day. Even though the lab sessions I did for my Cat-1 project was more sophisticated in nature, often involving bacteria, agar plates, extract, etc, one can argue that the practicals during Science lessons were a complete was of time.

I think what practicals can give us is confidence. By trying, even from the smallest of things, gives us the confidence that even greater things can be handled. If we have not even carried out practicals before, how will we have the confidence to embark on more sophisticated things? Practicals do serve their purpose, and whether we utilise its purpose, depends much on ourselves.

Reflection and Refraction

This topic allowed us to have a more visual approach when learning and approaching the topic. Reflection and refraction is actually not that hard if the concepts are understood, and by carrying out practicals, it enhanced our visualization and understanding of the topic.

The first and only time I calculated the refractive index was during the test. And the calculator kept saying error. As it is the first time the refractive index was calculated, I had no idea what went wrong.  I had no choice but the make an intelligent guess of the answer. I had guessed the correct answer, but written “B” like a “D”. Moral of the story? Write properly ><

On top of that, I would like to comment that the practicals were aesthetically pleasing to the eye as well. When we are done with the practical, we would play around with the lighting and set up and snap random pictures. Playing with light can be much fun after all. Do view some of the random pictures taken:

The part on real images and virtual images was rather confusing to begin with, and the notes did not define it well enough. Checking the net was the next option and I managed to get a better definition and develop a better understanding of the difference between real images and virtual images. Actually, the net can be great source of information for us, but it depends whether we bother to check it out in the first place. Science is a subject that involves a lot of information and knowledge that cannot be covered with only our notes, there has to be an element of self-learning in it. Maybe in the near future, we may rely a lot on our computer…

External Reading:

Well, who was the one which discovered the laws of reflection? Just a check on WikiAnswers and YahooAnswers, the answer is Rene Descartes. However, the discovery of the laws of reflection may date back even further- to the days of Euclid. 

Euclid states that:

1) Light travels in straight lines and will reflect from a smooth surface at the same angle with which it impacted it

2) Light is reflected in the same way that a ball would bounce off of a frictionless surface. Euclid claimed that light travels in rays that are discrete, like atoms but appear continuous, like waves, because they move so quickly 

If Euclid was the first one to make the discovery, then why do many think that it was Descartes who made the discovery? One possible explanation is that Descartes published an essay on optics and mentioned this law. In short, Descartes was the first person to publish on the laws of reflection, and most adopt his writing as the most plausible interpretation of the laws of reflection. 

Euclid

Rene Descartes 

Also, another thing I observed was that a particular scientific theory or law may go through many changes and improvements as time goes by. Take the laws of refraction for example. 

1) Greek astronomer Hipparchus compiled the first documented table of sine function before 125 BC. His work was referenced by Ptolemy over two hundred and fifty years later and so it is not known why he did not derive the sine law of refraction himself.

2) Ptolemy first tried to experimentally derive the law of refraction in the 2nd century AD

3) In 984, Ibn Sahl, a mathematician from Baghdad, discovered the law of refraction that Ptolemy had been searching for. Sahl showed that the angle of incidence is related to the angle of refraction using the law of sines 

4) The sine wave could not be represented graphically until the invention of the Cartesian co-ordinate system by French Philosopher Rene Descartes and French mathematician Pierre de Fermat in 1637.

5) The sine law of refraction, first discovered by Ibn Sahl in 984, was rediscovered by Dutch mathematician Willebrord Snellius in 1621. Snellius' theory was not published in his lifetime 

What can we tell from this? A particular scientific theory may need to be refined or improved as times go by. Issac Newton once said: If I have seen further it is by standing on the shoulders of giants. Perhaps without Ibn Sahl  or Snellius, would not have been able to publish the laws of reflection (or refraction). Scientific achievement should always be viewed as a collaborative effort rather than an individual effort. The scientist of today must thank their predecessors for making discoveries in which they were able to work upon or improve it. Imagine if fire was not invented...

Reproduction in Humans

Human reproduction is not something new to us. Having learnt it in primary school before, we had some background knowledge of it already. This time, things got a little more detailed, and the introduction of the menstrual cycle was the troublesome one.

Most of us leave primary school with a very vague idea of the menstrual cycle. All we knew was that sanitary pads need to be used, and that was more or less on what we knew. However, by adding the hormone level, it made the entire topic seemed rather confusing.

This was not the first time I was confused by the menstrual cycle. While reading What the Dog Saw by Malcolm Gladwell, unexpectedly, there was a chapter on the menstrual cycle. The chapter was titled “John Rock’s error: What the co-inventor of the Pill didn't know about menstruation can endanger women's health”. The chapter spent a fair share of time explaining about the cycle, the effect the pill has on women. While things were detailed, I could not understand a single thing. The nature of the topic was rather complicated. Well, I decided to move on and continue reading as there were other chapters that are less complicated, easier to understand.

When I was first handed the notes on human reproduction which contained the part on menstrual cycle, I was rather puzzled with it. As it was approaching the end of term, I did not clarify my doubts with anyone.

It was only one day before the Term 3 test that I started reading the notes (I was busy for the whole week due to council as well as other things) and looked at the menstrual cycle in detail. To be honest, it wasn’t that hard after all. Just required some detailed reading and understanding.

Moral of the story? Some things may be easier than they may initially seem, so do not cast any doubts on yourself even before doing it. I realize that at some point of time I was trying to escape from reality, I was telling myself it was hard to understand so don’t be too hard on trying. However, tests can be a great motivation. In the end, I managed to understand the notes.

You never try, you never know… 

Reproduction in Plants

Reproduction in plants is also not new to us. This time, things were explained to us in much more detail. The introduction of new parts of the flower such as the epicalyx and sepals was just some of the new things. Overall, I would say that the entire topic was not difficult and rather manageable as there was not much heavy content or studying to do.

The one-hour documentary shown (The Private Life of Plants) during lessons was eye opening. While we know that many flowers exist in nature, we are still unsure of the scale of the variety of flowers in nature. The documentary exposed us to many unique flowers that are worth taking a look. At the same time, the vivid images taken by the BBC crew deserve some credit.

I think that we do need to give some recognition to the production crews who took all the images and videos of nature documentaries that we all watch. While they are becoming easily available on youtube, we have not thought how difficult it is to produce a full-length documentary.  BBC has produced quite a few documentaries which are worth taking a look.  

We were handed a mushroom growth pack and told to grow our own mushroom. A worksheet was given to us to track and record the growth of the mushroom, and we had to fill in our reflection on the worksheet. I will not be writing down my reflection here, but to highlight something interesting I did to keep my mushroom alive. Ms Nada mention that the mushroom has to be water regularly, but I knew that was quite impossible in my case since I reach home at about 7 each day and leave at about 6.15. Next, the mushroom does not require lots of water, just some "misting" each time. In view of this, I placed the mushroom under a plant. I was hoping that the water vapour released by the plant would keep it alive and let it grow. True enough, the mushroom did grow. Looks like some creativity does work. However, the mushroom got infected some time later and the entire growth pack has to be disposed off.

External Reading:

Nature documentaries are exceptional when it comes to the stunning images of wildlife and nature. Regarding wildlife, violent scenes of lions eating animals, cheetahs chasing animals are often shown. Often we choose to believe that filmmakers put their life in jeopardy so that we as viewers can get closer to nature.

However, there have been claims that some nature documentaries, particularly those involving animals, have included footage of staged events that appeared to be "natural" but were contrived by the filmmakers or happened in captivity. The most famous example is Walt Disney's White Wilderness (1958) where lemmings were hurled to their deaths but there are examples in modern nature documentaries, such as The Blue Planet (2001). Series producer Alastair Fothergill admitted that around 2% of the whole series was filmed in tanks at aquariums.

In my opinion, nature documentaries would not have any purpose if filmmakers are making the documentary for the sake of making it. Documentaries are meant to enlighten and things are to be kept as authentic as possible. If a documentary is made under a controlled environment, then it would be very misleading to the viewer and instead of enlightening, mislead the viewer even further.

We have to admit that media has the power to influence people’s thinking, and it is important that they stand firm on their integrity and provide what is authentic. To all the filmmakers who maintain their integrity and principle in enlightening people on nature, deserve our applause. Next time, when I watch a nature documentary, it better not be fake….

Acids and Bases & Writing Chemical Equation

Again, acids and bases are pure memory work. The reaction between acid and carbonates, acid and metal, base and carbonate all needs to be memorized and no short cuts can be taken.

It was interesting to see how certain items which we consume or use on a daily basis are deeply related to acids and bases. Maybe it can be considered general knowledge, but I believe that it will aid us in one way or another if we have at least some understanding of acids and bases. One interesting application of Coke is to treat wasp stings. Coke contains phosphoric acid while wasp sting is alkaline. Bee sting, on the other hand, is acidic. Someone better teach us how to differentiate this 2 yellow insects…

This topic on acids and bases do require quite a lot of self study and not everything is provided in the notes. In the days leading to the test, I had to create this "Info Sheet" which contains relevant information such as examples of strong acids and weak acids, examples of bases, strong alkalis and weak alkalis, the formula for some solutions such as ammonia solution, or gases such as ammonium gas. As compared to the other topics which nearly all the information is provided in the notes, Acids and Bases is definitely more tedious when it comes to studying. Do we just sit down there and complain? Actually, there is nothing much to complain. It is the nature of this topic that requires lots of bits and pieces of information and knowledge here and there. We can't change the topic to suit our usual studying method of using only the notes, but we can change our studying method slightly to suit the topic. Change or not to change, it is actually quite a personal choice, which can be best reflected on the test paper. 

Moving on, writing chemical equation is not that easy, but it is also not that difficult as well. Not only does it requires understanding of the chemical reaction (between acid and alkali for example), it also requires us to identify whether this particular substance is acid, alkali, metal, base, etc. After that, we have to ensure that the equation is mathematically correct by making the equation balanced.  Writing chemical equations does require some amount of practice to master it. 

Is there a link between Acids and Bases and Writing Chemical Equations? Certainly there is. If there is good understanding of acids and bases, like the reaction between acids and metal, acids and carbonates, for example, then our ability to write chemical equations would definitely be much faster and accurate. 

Atomic Structure & Periodic Table

When the periodic table was first introduced to us, we have to admit how limited our knowledge on element was, or rather how science has endlessly continued to develop. As all kids would have taught, the proton number was just a label for the element and had no specific use or reference. How wrong we were..

The entire part on Atomic Structure and Periodic Table was pure memory work and understanding. My mum always tells me that subjects like Science and Math require lots of understanding and practice. And honestly speaking, not having the luxury of time, the least I could do was to understand. The practice which I had was rather limited and constrained to class assignments, with no additional exercises on my own. This can be seen from my test marks ><

Tests aside, the interesting thing about this topic would be drawing the electronic structure. It was different as it provided a more visual approach in our understanding of the chemical bonding.

Isotopes are just an example of how Science can be a blessing as well as a curse for mankind. As much as scientific discoveries aim to improve the standard of living and improve mankind’s prospect, it can prove detrimental to mankind if not used properly. This shows the power of science- the power to affect humans, for better for worse. Therefore it is important that scientists are responsible people who act in the best interest of mankind.

External Reading:

Well, there has been some talk about negative ions being healthy in some ways.  It was never mentioned anywhere that ions will cause any effects to human health-until I was exposed to the above concept. There are currently products that releases negative ions to achieve the desired effect as claimed. Does negative ions make one healthier to any extent?

Feeling somewhat curious, a little research was done online. I found this article rather useful in providing an answer.

http://www.webmd.com/balance/features/negative-ions-create-positive-vibes

One question leads to more question. The article, instead of providing a substantial answer, provided a rather vague and unclear explanation of negative ions and its effects. Now, there are even more questions than answers in my mind.

Firstly, antidepressants contain chemical or certain elements that give it its effect. Technically speaking, when an ion becomes an anion or cation, no other elements would be produced as a by-product other than the 2 given elements. So which aspect of negative ions enables it to have an antidepressant property?

Secondly, under what conditions would elements remain as negative ions? According to the article, it suggests that radiation from sunlight can also result in the creation of negative ions. Is solar radiation some form of catalyst that aids the formation of ions? Next, the reason for the formation of ions is so that there can be bonding between a positive charged and negative charged ion. Therefore, an atom would not gain an electron for the sake of gaining one, but rather to bond with another atom. In this case, there would not be any negative ions lingering in the air, as they all would have been bonded already.

With questions come even more questions. Should it be this way? Well, I think that being inquisitive to a certain extent would be good. After all, the ability to question what is taught or read  shows that one is truly thinking and making judgments, rather than absorbing everything that comes in the way.