WATER!(:

24th March.

We had a rather exciting lesson, with the bee and all.

We were asked to write down what came to our mind when we thought about water. And we came up with things like AQUA, rain, rivers, ice and even things like pee, just to name a few. I guess this was to have an idea of what we think water is all about right at this moment before we learn anything more about it. (I don't have a picture of the stuff we wrote on the board!)

We were given a reading which was (to me) a rather big mix of chemistry, physics and even a bit of biology. It is rather cool to understand that water when frozen has a lower density as compared to water (in liquid form) so it floats and so it freezes only the top layer! By only freezing on the top layer, our dear water creatures can still live because the rest of the water isn't frozen.  Other than that, we also learnt that water is a versatile a unique molecule that is compatible for life. Water has a range 100 degrees Celsius in liquid form. And as Ms Tang said, since we are made up of 70-80% water, imagine if the range of water in liquid form is like most liquids at a range of about 20 Degree Celsius, standing out in the sun could just cause us to evaporate or experiencing winter could cause us all to freeze and become ice blocks. I really am starting to appreciate water now. [Of course, this is another reason why we should all save water.]

The specific heat of water, which is the amount of energy required to raise the temperature of a substance in this case water, is particularly high as compared to other liquids for life. It is harder to raise the temperature of water. And as we know, large portions of the Earth is covered with water and not forgetting that the changes in temperature of water bodies could result in widespread flooding, melting of glaciers. Thus, the specific heat of water helps to maintain Earth's fairly stable climate.

Another interesting fact is that water is a universal solvent! Many substances can dissolve in water.

Now we know why water is so essential for life!(:

Then we went to somewhere behind the classroom block to talk about drainage basins. In my understanding, a drainage basin is an area where water drains downhill into a body of water. So there has to be

1. water

2. relief (so the water can flow downwards)

3. land (can be soil, concrete, anything. It does not have to be of common material)

The water can fall in any part enclosed within the dotted lines and it will flow to the bottom. The brown dotted line is an imaginary line that roughly marks out each drainage basin. This imaginary line is called the water shed.

That's all for the lesson!

Shanice