Term 3 Results Reflection

I have done better than last term but its still not that good yet. I guess I just have to try harder in the EOY exams. Hope I do well, I really do not wish for a repeat of  Term 2. I was really upset!

Term 2 Results Reflection

I am even more disappointed in this term's results than term 1. This is as my results disimproved while my whole class has improved. I have never felt so much determination to do well since PSLE.

Term 1 Results Reflection

I feel that my results were relatively poor this year as I had not studied hard for it. I only started preparing the day before. Also, the fact that I had not much idea of what to study was probably a big factor. All in all, I am rather disappointed with my term 1 science results.

Plasma

This is a report I did for my ACE which tells us more about this fourth state of matter :


Introduction
Plasma is the fourth state of matter and is basically an ionized gas which has properties that are unlike those of solids, liquids or gases. Thus, most people consider it a new state of matter. Plasma was first discovered by Sir William Crookes in 1879 but he did not identify it as a fourth state of matter. Subsequently in 1897, Sir J.J. Thomson discovered the nature of Crookes’s discovery as a new state of matter. Finally, it was dubbed "plasma" by Irving Langmuir, who most people consider as the man that discovered plasma, in 1928.
Differences from other states of matter

1.    Molecular level

·         Solids molecules can only vibrate in place in a relatively slow motion

·         Liquid molecules can slide over each other and move around faster than solid molecules and the space between the molecules also increase

·         Gas molecules move much faster than liquid molecules and they can move all over the place in a random motion

·         The molecules in a plasma are even faster than gas so much so that they come apart and the nuclei are separated from the electrons

2.    Properties

Ø  Density

·         Solids generally have the highest densities

·         Liquids generally have lower densities than solids

·         Gases generally have even lower densities than liquids

·         Plasmas generally have the lowest densities

Ø  Shape and volume

·         Solids have a definite shape and volume

·         Liquids have no definite shape but instead takes the shape of its container, and they have a definite volume

·         Gases have no definite shape and volume, thus it will take the complete shape of its container

·         Plasma is similar to gas in this area

Ø  *Temperature

·         Solids are generally cooler

·         Liquids are generally warm

·         Gases are generally hotter

·         Plasmas are generally the hottest amongst the four

*The differences in temperature can be linked with the differences on a molecular level as the hotter the matter, the faster the movement of the molecules
*Although plasmas are generally the hottest, there is a type of plasma called ultra cold plasma (not to be confused with cold plasma) which are even cooler than most solids however these are only the minority and are man made through experiments
Examples of plasma
There are not many types of plasma on Earth but there are a few that are quite common such as fluorescent lights and neon signs. Unlike normal light bulbs, fluorescent lights they do not have filament in them but instead, they are filled with gases that get ionized and turn to plasma when the light is switched on and the electricity flows through it. Neon signs follow the same concept. They are also used in the making of plasma TVs. The Sun, the stars and even lightning are all examples of plasma. Although there are few types of plasma on Earth, about 99% of the matter in our universe is in the plasma state.


This is a picture of plasma

This is a picture explaining how the neon lights work

The Acid Sea

This is an article I read in the National Geographic Magazine about Carbon Dioxide, and strangely enough, it is about the sea and not the oh so famous Global Warming. Anyway, it all begins at Castello Aragonese. The sea around island, thanks to some "quirks of geology" as the magazine puts it shows us what the sea would probably look like in the 2050s and beyond, and its not pretty. Almost every single living organism was absent, snails, corals, sea urchins, barnacles, all gone. All that remained were sea grass, jellyfish and algae. And I almost forgot, Carbon Dioxide bubbles that steamed up from the sea floor. The cause of all this, is Carbon Dioxide. Carbon Dioxide dissolves in the sea to form carbonic acid, after all, we drink it all the time in carbonated beverages like coke. However, if enough of it forms, it is enough to make sea water corrosive. Furthermore, when you get it to an extremely high level, almost nothing besides jellyfish, sea grass and algae can stand it. Over the past 2 centuries, the oceans have absorbed 30% of the Carbon Dioxide released by us. This may be a good thing for us as every ton of Carbon Dioxide the sea absorbs, is every ton of Carbon Dioxide that is not contributing to Global Warming but as for the aquatic life on Earth, it is quite a different story. However, this does not mean that we get off Scot-free, after all, this would affect the availability of certain nutrients provided by aquatic food like iron and nitrogen. All in all, this is a new problem that not many are aware of yet and needs to be taken more seriously. After all, Global Warming is not the only big problem we should be worried about.

This is a picture of what the ocean floor looks like now

This is a picture of what the ocean floor is expected to look like in 2100

Diffusion and Osmosis

Diffusion is the net movement of particles from a region where they are at a higher concentration to region where they are at a lower concentration. ( Definition from notes )
Osmosis is a special type of diffusion, it is the diffusion of water molecules through a semipermeable membrane. So basically, if it is not water that is being diffused and there is no semipermeable membrane, then it is not diffusion.
This is one of those topics that I really had no idea existed until I was taught. Thus, when the teacher asked me to define the meaning of diffusion and osmosis, I just said that I did not know. However, once you understand what they mean, this topic gets a lot more easier.

This is an example of osmosis, a special kind of diffusion

Separation Techniques

There are many different separation techniques and they include simple distillation, fractional distillation, evaporation, filtration, magnetic separation, heating, passing an electric curremt and chromatography. Those were the separation techniques taught to us but as for others, they were not taught yet and so I cannot really name them.
This is linked to mixtures and compounds but is basically purely focusing on how to separate them. Physical methods are for mixtures while chemical methods are for compounds. However, we only focused on physical methods in class and practicals.

This is an example of fractional distillation