Hey, welcome back; I am glad to see that you have not lost interest yet. Now where did we leave off? Oh Yea, that hydrogen atom, and the different ways that it bonds to other atoms. I suppose we should cover the subject of water. Actually that makes sense because we all know what water is. We drink it, swim in it, bath, cook and clean with it. It also falls from the sky as rain, and can make our fish happy.
Now we are covering the subject of pH not Alkalinity. So in order to do this we need to understand that what I am about to discuss is about PURE water. Not water from a Reverse Osmotic system, or from the tap, or spring water. I am talking about pure 100% water.
Now with in pure water all you would have is hydrogen and oxygen atoms joined together. But why are they joined together?
Water has a unique structural and chemical property. However, we have to understand hydrogen bonding. This is just one of the ways atoms join together to form compounds or chemicals. The other two forms of bonding are by ionic and covalent bonding.
Its important that we talk about things bond. Take a look back at the electron orbits of atoms. Remember when I mentioned something about orbital shells. Well this is where the story gets interesting.
The orbits of electrons around their atoms are well known. Scientists know how many electrons can occupy an orbit; they know how far away one orbit is from the next and how many electrons can be carried in each of those orbits.
Okay, now lets think on bigger scale. Take the Earth and the Moon for example. The moon orbits the earth. Now think for a moment, and what is the first thing that comes to your mind? Chemically speaking of course. What does it remind you of? Did you think of the hydrogen atom? If you did, good for you! That means that you are still with me. However, for the hydrogen atom, as well as all other atoms, this orbit is known as a shell. In other words just a path that an electron would take if it were in orbit around an atom.
This one shell or orbit, and I am going to use the word shell from here on out, can hold up to two electrons. Okay lets make you think here for a second. What planet, which circles the sun, has two moons? Did you think of Mars? Well if you did GREAT, if not its okay, not to worry. But Mars has something in common with the first electron shell. Mars has two moons. The most electrons that can orbit in the first shell are two. Thats it, no more.
So we go back to the basic hydrogen atom. Take into consideration what was said before, and we now know that the hydrogen atom can have up to two electrons in that shell.
Now when a hydrogen atom meets up with another one, they join. When they do they begin to share their electrons. So in essence they fill that empty space in the orbital shell.
This is known as a covalent bond. Two atoms sharing one or more pairs of electrons form a covalent bond. Covalent bonds are strong and more common then hydrogen and ionic bonds.
Ionic Bonds are bonds that are electrically neutral. This is when the number of electrons equals the number of protons with in the molecule.
Okay lets tackle a new chemical that we are all familiar with because it makes up one part of the table salt that we use. Sodium, which is indicated on the periodic chart as the symbol Na has the following characteristics.
- Atomic Number 11
Atomic Weight 22.989
Sodium has 3 orbital shells. Okay we know that the first orbit, the one closest to the center of the atom can have up to 2 electrons, that you should of gotten right, or at least predicted the answer. The Middle shell has and can hold 8 electrons, the third shell can hold 8 as well, but the sodium atom only has 1 in its outer most shell. Okay, how does this relate to what we have are talking about.
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