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Everything You Ever Needed To Know About pH

Part I: Quick Review of Basic Chemistry

From Thomas Hynes, for About.com

Contributed by: Thomas Hynes

When people think of pH most may think of whether a liquid or another sample that is measured is either alkaline or acid. However this is really not the correct way to think of pH. In order to get a better understanding of what pH really is, it is necessary to review some basic chemistry.

Hydrogen, the most abundant chemical in our universe, is quite a remarkable thing. It can bond to other chemicals such as oxygen giving us water, or bond to itself giving up hydrogen gas. Along with these configurations there are isotopes of hydrogen as well. But before we get in too deep, lets review the hydrogen molecule.

Molecules are made up of three things.

    1: Electrons
      Electrons are small tiny bits of matter that carry a negative charge, they orbit protons and neutrons, and these orbits are known as orbital shells.
    2: Protons
      Protons are larger than electrons, yet their charge is positive.
    3: Neutrons
      Neutrons are particles that carry no charge, they are neutral and can be found right next to the protons in a molecule.

So there we have it, three basic units that make up all atoms and chemicals. Well not really, there are smaller units yet that make up electrons, neutrons and protons, but since we will not be discussing quantum mechanics, there really is no need to delve deeper into the theoretical ideas of physics and chemistry. There is one interesting piece of information that can be shared though. For all you Star Trek fans out there, I am sure that you are well aware of antimatter. Antimatter does exist in extremely small quantities, and scientists have used these to carry out other interesting experiments in the world of quantum physics.

A molecule of antimatter is nothing more than the same electrons, protons and neutrons that make up an atom, except that they carry the opposite charges. Hence the electron would have a positive charge, and the proton would have a negative charge. That poor lonely neutron we talked about, well it’s neutral in charge, not being positive or negative, so it remains the same in the antimatter world.

So lets get back to the hydrogen molecule. Remember that big chart in the science rooms with all those letters and numbers and boxes on it. Well that’s known as the periodic table. And all those numbers, and symbols mean something. Since we are just talking about hydrogen for now lets take a look at what it all means.

Hydrogen is the first element. You may wonder why this is? Well its because as a single atom it has the lowest weight, atomic weight that is. Yes, even though these particles are as small as they are, they have mass therefore they weigh something. Hydrogen is listed as H on the periodic table that’s pretty easy to understand.

Here are the other little known facts of hydrogen:

Atomic Number = 1
Atomic weight = 1.0079

Notice that the atomic number is almost the same as its atomic weight?

Electron Configuration = 1s1 (a bit more on this later).
Melting point = -259.34C
Boiling point = -252.87C

Just interesting, little known facts to help you with that Jeopardy Question!

Next Page > Page 2: Quick Review of Basic Chemistry

Part II: Quick Review of Basic Chemistry
Part III: Quick Review of Basic Chemistry

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