Chemical bonds

Hi,
this post is just a systematic list and explanation of chemical bonds because I needed to learn them for chemistry class and at the same time, why not make a post from it?

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Chemical bonds are bonds between two atoms. There are various ways in which they can “connect”, and that is what this post is about:

Covalent bond

Covalent bond is bond between two atoms which causes sharing of electron pairs. The difference between electronegativity is less than 1.67. If it would be bigger than the bond would be called ionic bond. Covalent bond is always going to be between two same atoms, for example H-H or   C-C and so on.

EDIT (18.2.2016): Also if the difference is less than 0.4 the bond is nonpolar while if it is between 0.4 and 1.67 it is polar bond. This is important when you want to dissolve some stuff because only polar things with polar dissolve and nonpolar and nonpolar while not polar and nonpolar. For example water has polar covalent bond because the difference is roughly 1.2 or so.

Ionic bond

Ionic bond is extreme case of covalent bond since the difference between electronegativity of two atoms is greater than 1.67. This means that one atom is going to attract the other electron so much that the first atom wont even hold it anymore. Examples of such cases are: Na+ and Cl– or Li+ and F– .. this “plus” means that the electron was moved a lot towards the other atom while “minus” means that the atom has a lot greater electronegativity and is able to catch this electron causing the atom to be negatively charged.

Above you can see how atom of fluorine takes one electron from lithium under his control (red arrow). Such molecules are easily dissolved in water and they are called non-polar molecules.

Dipolar bond

Dipolar bond is very similar to covalent bond and it can create when one of the atoms do not have any free electrons while the other one has two in one orbital. One of them then may move to the first atom and create bond with the other electron which is alone now.

Because bond can always create from electrons of opposite spin, with dipolar bond you can be sure that it will create because both the electrons came from one orbital so they have to have opposite spin.

An example of such a bond is NH4. Nitrogen has three orbitals ready to be connected with hydrogen which happens. Then the last hydrogen is actually H+ so he does not have any electron but nitrogen can share both his electrons from 2s2 orbital as you can see on the next picture. Here nitrogen is called “donor” and hydrogen “acceptor“.

Metallic bond

Metallic bond is very often seen on metals and it is the reason for their thermal and electric conductivity. As you can see below atoms are all positively charged, which means they are cations while their electrons keep flying around making what is called “electron gas” (as you can see on the next picture), that is why the current so easily “flows” through metals.

Dragallur

3) Particles: Quarks

Hi,
I have been writing about quarks a lot so now I would like to shortly summarize what they are.
Quarks have been discovered when scientists saw that paths of particles traveling close to neutron are distorted by some weak electromagnetic field. Then they discovered that neutron is neutral but it contains particles which are not neutral: quarks.

If I told you that protons and neutrons are only made up of three up and down quarks  you could easily figure out what is inside them. Proton´s charge is +1 which means there has to be 2 ups and 1 down because UP(charge)=+2/3 DOWN(charge)=-1/3 === 2*2/3+(-1/3)=+1. While neutron is made up of two downs and one up which equals to 0.
As you can see from the table there are six types (flavors) of quarks. I talked only about two of them because they are much more common then charm, strange, top and bottom. The reason why those four are less common is that they are extremely heavy compared to up and down quarks and they will decay into up and downs. Up and downs can not decay to anything which makes them stable. Even then it is thought that proton (uud) can decay.. I talked about it earlier so you can check my other posts.

Flavor is one attribute but there is another. I mentioned it in post about strong interaction and it is color of quarks. There are three “colors”: RGB — red, green and blue and antired, antigreen and antiblue. Those colors always have to add up to white color. There are lot of combinations which can do this – RGB, antiRantiGantiB, blue and antiblue, red and anti red… and many others

It would be far too easy without gluons which are holding quarks together.
They are usually drawed as a short string between quarks. The thing that they do is color changing. They do it at two points: when they enter and when they leave quark.
There is hypothetical astronomical object called Quark star which should be made up of free quarks. Also it is thought that right after big bang there was state of matter in the Universe called quark-gluon plasma… soup of free quarks and gluons. We are not yet able to create this because it probably needs extremely high temperatures.
On the left is a picture which compares mass of quarks. On the botom you can see grey proton and really small, red electron. Top quark is the largest one.

Particles which are made up of quarks are sorted into different groups: mesons and baryons you can see on the picture what they can look like and how colors add up to white.

Dragallur

1) Particles: Prologue

Hi guys!
I am back with probably short post because I am lazy and tired these days. I know I wanted to start something about triangles but right now I am not that excited for it so I will make some posts about particles. I talked about some before but I have never explained what the hell are quarks for example.

So first of all… particles. Well we think about them like small stuff that is everywhere and everything is made up of it. That is right.
So I will start with molecules, easy peasy those are just two or more atoms made up together.
Atoms are (small), there is some stuff in them but first of all there are “kinds” of atoms, substances and that is Hydrogen, Helium, Oxygen, Carbon. They are made up all from the same things but with different amounts. Atoms are made up of core and shell. Usually, you wont do anything with core. It is very stable and not interacting. In our organism there are only changes in molecules. That means that some atoms will move somewhere else and that will change molecules properties.
Shell is made up of electrons. Electrons are NOT made up of something else, it is just primal stuff. Electron belongs to group of particles that are called elementary particles. It´s sub-group is called fermions and its sub-sub-group is leptons which are really small and light.
Core is made up of neutrons and protons. As I talked about them in four fundamental forces series those are particles (sub-atomic) that are hold together by strong force. Anyway protons are positive and neutrons neutral.
There is huge experiment going on in Japanese which is trying to proof that protons are decaying. Its problem is that one proton has half time about 10^31 years long. They did nice trick so they do not need to wait so long by monitoring ultra clear water. There are thousands tons of water and their machines are able to detect any proton decaying to photons.
Photons are also elemental particles but their sub-group is special for particles that are carriers for fundamental force: photon, gluon, bosons but not graviton because he is only hypothetical. Photons are massless which is why they can travel at the speed of light.
At last for review there are quarks which are elemental particles, even fermions like electrons but they are in special group for quarks.
I actually read something about quarks not being elemental (only hypothetical). It was said that if they are not elemental we can not be sure that there is unlimited number of smaller and smaller particles.

This was just a short preview of what I will write about next time.
Dragallur

5) Four fundamental forces: Strong interaction

Hi there!
I am back again! I was very sick with great temperatures but now I am alright with idea what to write about so I am bringing probably the last post for four fundamental forces today with strong interaction as the strongest of all forces.

Again on the left I have here proton. There are two parts of strong interaction, first is color force which is the stronger one and it holds particles, like hadrons (particles made of quarks) together. You probably heard of colors of quarks, there is green red and blue (RGB) and in such particle like proton or neutron those colors always have to add up to white color. If it would be antiparticle it would have anti red, anti green and anti blue.

Again on left you can see how these colors add up to white. Well what happens is that there is gluon, particle which is carrier for strong interaction and it jumps from quark to quark and when it touches it changes its color. There is great animation in this video, I recommend to watch it: https://www.youtube.com/watch?v=BNDOSMqGLlg
This color force is extremely strong so it does not let quarks to go apart. It is even that strong that when you break it new quark will be created from that huge amount of energy! Scientist think that right after big bang when particles were really fast and close to each other there was state of matter called quark-gluon plasma which was kind of soup of quarks and gluons. It is hypothetic and it was not yet created in LHC or somewhere else.

There is that second part of strong interaction called: nuclear force. I am not really sure about it, but anyway you maybe wondered why does nucleas exists when protons(+) should repell each other and that is made by particles called pions which are carrying quarks around and they are creating reaction which is attractive.

On the end, pions are particles made up of two quarks but one of them has to be antiquark so they looks like this:
There are three types of pions and those are Pi+, Pi-, Pi 0. Their life time is incredibly short and they are decaying to neutrinos or gamma rays.

That will be all,
Dragallur
PS: Thanks for your likes and comments

3) Four fundamental forces: Electromagnetism

Hi guys,
today I will return to electromagnetism as second fundamental force.
It is made up two forces which we are thinking like extremely different ones.

First I will talk about electro static force.
Well, It is quite easy. When you have two objects and one wants to give electron while the other would like to take some electrons and you will make them touch each other electrons will be jumping there creating one object negatively charged and second one positively charged. (F.g. when you pull your christmas sweather on you, in dark you can probably see little lightings and feel those small shocks.) It is the same wiith battery, one side wants to have electrons so when it is charged it does not have them while second one has lot of electrons but it doesn´t need them so through some wire this difference will be slowly going to equalize by flow of electrons.

Magnetism also works with electrons and that is why these forces could be connected to electromagnetism. Magnet is made up by some special material in which atoms are turning by their pluses and minuses. So in every magnet there are millions of magnets. It does not matter if you make it smaller there will always appear new south and north pole which is made by this turning of atoms.
+  -+  –
+  –
+  –
+  –
Here on right would be south pole (+) and on left would be north pole. It it would be really light (not heavy) and it could easily turn it would be kind of compass.

At last if teacher told you that others things that are not created by Fe,Co,Ni cannot interact with this force they are wrong because you can actually find videos of levitating strawberries because of extremely strong electromagnetic field.
There is also very special attribute of electromagnetism, if you have wire without elctricity and magnet somehow rotating around you can create electricity.
That is way to create elctricity for your house. For example water flowing rotating turbine and magnets around wire is way to get energy. Or by wind rotating turbine or hot H2O flowing in reactor.

Thats about it.
Dragallur