25 Mayıs 2017 Perşembe

what is electric electricity, why metal in electric

What is electricity?
                Electric is basically transporting the energy produced bu any kind of energy source; with the help of electrons in the atoms. Electric itself is not an energy. İn todays technology energy is not something we can hold or store or use directly. We transfer the energy of a source to a carrier then we can use it. As an example coal is an energy source but we cannor use or hold yhe energy hidden in the chemical structure of coal. We burn the coal to rlease the energy of the molecules to gain energy as heat. Then we make steam by heating water. Then hot steam is used to do things needing energy. İn this example energy is in the form of heat, source is coal and the energy transporter is steam. After that axample it is easily to be said that electric is the way of transporting energy like we did and still do with steam. Instead of energy loaded water molecules energy loaded electrons flow through the system.
                Lets use another knowledge to make another starting point. All matters/materials/ physical beeings are formed of atoms. Atoms are the basic components of everything we can fell with our senses. At the center of the atom there is the nucleus of the atom. The nucleus is made up of positively charged protons and neutral neutrons. Almost all of the weight is condensed in this very small piece. On the perifer of the atom there are electrons which are negatively charged and considered as weightless. By the help of these advantages electrons are always on the move through certain orbitals. However protons and neutrons don’t do that. They can only vibrate in the nucleus which is practically nonsense in electricity.
İf anyone could have seen the movement of the electrons probably that one would say that electrons move randomly. However they do not. Like planets moving around the sun or the satelites moving around a planet, electrons have relatively certain orbits also. As a difference electrons orbitals are more circular and their speed is almost equal to the speed of light. Electrons can be such free because they are almost weightless. The weight of an electron is 1/2000 of a proton. A proton is a lot smaller than we can imagine. How ever electron is 2000 times lighter than them. So they are much more free in the atom. 
For a beter explaqnation we can imagine hydrogen gas atoms. A hydrogen atom consists of only 1 proton and 1 electron. Since electron is practically weightless atomic weight of hydrogen is practically equal to the weight of proton. One gram of hydrogen consists 6,02*10²³ hydrogen atom. İn other words 602 000 000 000 000 000 000 000 adet hidrojen (practically proton) is only one gram. So one proton alone is 1/ 602 000 000 000 000 000 000 000 of a gram.
In a universe where measures are that small an electron is approximately 1/2000 of that measure. It is practically nonsense to make calculations that difficult where these differences do not mean anything practically.
After all, some chemistry from high school: all atoms have different numbers of electrons and these electrons make their movements in certain orbital routes. This means atoms have 3 dimentional shapes. As known commonly the strongest 3 d shape is sphere. So every atom basically wants to be in a perfect spherical form. And try to be so.
In atomic universe this perfect spherical shape can happen only when there is 8 electrons in the last orbit of the atom. It is nonsense to make the schrodinger calculations here. That is unecessarly complex fort he end point users like us. But as a summary we can say that if there is 3 or less atoms in the last orbit of an atom, that atom is a metal and that atom will tend to give these excess electrons instead of gaining new ones. Giving out 3 electrons is much easier than getting 5 more from other sources. The opposite is true in another way: if an atom has 5, 6 or 7 electrons in the last orbit; it is an ametal (or non-metal) and that material will prefer to get electrons from other atoms instead of giving them out.
The atoms having exact 8 electrons in the valence orbital (last orbital is called valence orbital) are noble gasses. Since they have the perfect architectural structure in atomic universe they are do not intend to relate with other atoms to make electron transport. Also there are only 8 atoms in that noble class and they are all gasses. Because of that we will not see them much in daily electric.
The atoms having 4 electrons on the valence orbital can either take or give electrons. Because of that they can act very different in different enviroments. There are only 4 atoms in that form and the intentions of each of them are so different that usage of these materials have unique properties. For example pure carbon can both give and take electrons and surprisingly the number of transferred electrons do not need to be exactly 4. Less or more than 4 electrons can be transferred and the energy needed for neither gaining nor giving out is almost equal. So the tarnsfer can work in both ways. Because of that carbon is mostly used in several battery types. However silicon has also 4 valence electrons but less intent to transfer electrons. So silicon is used in circuit parts in order to control the flow of electric current.
Another subject to be mentioned is affinity of the atoms to electrons. The less the number of electrons in the valence the more affinity to electrons. As an example an atom having only 1 valence electron has more intence to give that only electron out then another atom of having 3 valence electrons. İn another words an atom with less electrons to transfer can do that faster and stronger than that with morfe electrons. Like sodium has only one valence electron and aluminum has 3 valence electron. Sodium can give its electron many more faster than aluminum and sodium is much more dominant in such a trade than aluminum.
The opposite is also true. An atom having 7 valence electrons need only one electron for a perfect spherical shape. And these atoms have more affinity to electrons than that of 6 or 5 valence electrons. As an example chlorine gas has 7 electrons and need only one electron to be a perfect sphere. Nitrogen has 5 valence electrons and need 3 more electrons fort he spherical shape. Because of that free chlorine gas can easily react to almost any material even in room temperature however nitrogen needs the power of a thunder to make the same electron trade. This affinity difference is the basic of the batteries.
All metals intend to give their electron but this is not always that easy. For example cupper has only valence electrons but the atom itself is so big that cupper atoms can not get close enough the gaining atom to maket he transfer. As another example aluminum is a relatively smaller atom but it has 3 valence electrons. The atoms that can take 3 atoms at the same time have less affinity. So the nitrogen which is capable of getting 3 electrons at the same time and the aluminum on the ground do not form aluminum nitrogenate. The atoms which are capable of gainin one electron at a time, have more affinity but this time the probability of being a 3 valence material and a 1 valence ametal at the same time at the same place with the same amount of energy   is so low that aluminum chloride is also so rare in nature. Same calculation is valid with the 3 valence metals and 2 valence ametals like aluminum and oxygen in the air.
That kind of metals cannot give their electrons easily bu they are very unconfortable with these valence electrons. Because of that they set their elecrons free. The electrons can move freely in the atom in most metals. Actually a metal is like a sea of freely floating electrons with the islands of nucleii. However the nucleus is stil powerful enough to hold its electrons closer. Yet valence electrons have more permission to float; more free to move further. Although all metals can do that; aluminum, cupper and some such metals are more important in electricity. Because of that ı gave examples of them.
The freely floating electrons sea still has an order and nucleus is stil powerful enough to hold the electrons close but this bond is not as powerful as the ametals. These floating electrons can easily be taken away from the authority of the nucleii (nucleii is the plural form of nucleus. It is like saying nucleuses). Because of that phenomenia, applying a constant magnetic effect to the metal roll from different dimentions like a Rolling system you can manage to push all the electrons moving to the same direction. Which is called electrical current. This is accomplished about 150 years ago by building both dynamos and alternators to produce electric current.
By the help of that floating electrons idea metals can easily let their electrons to flow to the direction of the current. Because of that metals can transfer electricity. Every metal atom have different resistance but all can do that. Thats why electric wires are made of metals. Especially copper and aluminum is used because they are cheap enough, it is much easier to put them in shapes, both have beter flexibility and as in the given examples above cupper and aluminum are more resistant to oxidation. So they can have a long lifetime when installed.

İron could be used for wiring but it can be oxidized much faster and is much heavier than both cupper and aluminum. Also gold and silver are a lot less resistant to electric flow but are much much more expensive. Titanium can be a good material with beeing less resistant to electric and having less weight than most of the metals. However it is very hard to shape titanium and that is why titanium is used in high physical ressistance systems like space crafts.

 






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