Sunday, January 23, 2011

Water , water everywhere !!

Water Molecule





We are blessed to exist on a planet that is covered with so much water. As a species we evolved here on earth, as such a good percentage of our physical makeup is water. It has been said that if you remove the water from our bodies there would be left, at most a few kilograms of common elements. In a Star Trek the Next Generation episode there existed microscopic life forms. These life forms were very intelligent and learned how to reconfigure the universal translator. After they had scanned us they called humans, giant bags of mostly water. Well not the most flattering description, but very accurate.

Water is so common that we often do not give a first thought , let alone a second. There is an abundance of salt water. Fresh water, because of our disgusting habit of pouring filth into it , is becoming harder to find and even harder to keep clean. Water is composed of two elements. The first is the most common element in the universe. It is the very first element found in the periodic table; hydrogen. The second element is one thing we need to survive. We literally could not take a breath without it. It is of course ; oxygen. The latter element tends to react well with some elements. One such element that reacts is iron, known by its chemical name, ferrum, and it produces ferric oxide, otherwise know as rust. Here is an example that can be used to see this action. The next time you eat an apple do not throw away the remaining core. Leave in a place you  where can observe it. In just a few minutes you will see the surface slowly change colour. From the pure white, a brownish-red colouration appears. Apples are a rich source of iron, an important nutrient that forms part of our blood. When exposed, by removing the outer skin the apple begins to rust. Quite fascinating when you think about it.

Now water is also know by its chemical name H2O. Ice , as frozen water is a solid and is less dense than the liquid and floats at the waters surface. As such on the very cold days ice will form on rivers and streams , however it will not freeze completely through. Think about this, the life that exists in the water, such as fish can still swim. Have you ever observed how water freezes ? It begins to form long needle like structures. They form all over the place and grow and grow to cover the entire surface.

I  have always wondered why, when I used to leave a dish with sticky, hard to remove food that seemed glued to the side of the dish, in water overnight, was easy to clean the next morning. It was not until high school that a wonderful chemistry teacher, Mr. Westwater told me the reason. Please look at the diagram that begins this piece. The the atoms line up in the water molecule is similar to a big ball, which is the oxygen atom, with two little balls, the two hydrogen atoms, that bunch up at one side. This happens because of the nature of the chemical bond. Note the ions have a charge before they join. The oxygen ion is negative and the hydrogen ions are postive. Now the water molecule has no charge, however look at the way it is configured. As such one side of the water molecule is ever so slightly negatively charged, while the other side is ever so slightly positively charged. The assumption is that food particles, made of complex and simple compounds also have small charges associated with them. During the night the water molecules are attracted to the food particle and attach. Even in a small dish ,at room temperature the huge number of water molecules are attracted , jostled, replaced. In a few hours the particles loosen up nicely.


Did you know that you cannot compress water to a great extent. Think of that the next time you water the lawn. The surface tension in water allows you to float a metal paper clip. This same surface tension allows water to creep up small, narrow tubes. In this way plants and trees can take in the water they need to survive.


So in conclusion even the simplist of things is truly fascinating. I feel that this simple, common compound connects me to the microcosm that surrounds us all.
    

Thursday, January 13, 2011

Here is a video of my Robot Tipsy. He is one of the older BEAM robots I had built a few years back. He worked ever so well and I would feed him with light and he would run ever so slowly. Unfortunately I moved from the basement to the top floor of my house. In the process of the move Tipsy hit the ground so hard that he broke. After almost a year I repaired him. One day I noticed something the basement could never offer , bright I mean really bright sunshine. So I rigged a very shakey platform and watched as Tipsy moved. His solar panel loves the sun and he triggers so quickly that it suprised and delighted me. As you can see he went faster than I thought he would and fell. However he was alright though it took me a little longer. The reason I call him Tipsy is that in his present configuration he has a tends to tip over.