A On this day in physics: 22 February 1857- Happy Birthday to Heinrich Hertz who would have turned 159 today. He was a physicist who first proved the existence of electromagnetic waves. He is also the namesake for our unit of frequency, the Hertz.
Word of the day- Ion- An ion is an atom which has fewer electrons than protons, or more electrons than protons. We like to think of most atoms in their "steady state" as having an equal number of electrons orbiting the nucleus of protons and neutrons. Because there are an equal number, the amount of positive and negative charges cancels out, leaving a net charge of 0. However, this is not always the case. There are negative ions and positive ions, which can be highly attractive to electrons or other atoms, in an effort to create a situation where the net charge is zero.
Example: Sodium Chloride, or NaCl. Sodium, or Natrium (hence the Na), is an atom which can come in the flavor of a positive ion, with one fewer total electron count than proton count, giving a net charge of +1. Cholrine can come in the flavor of having one extra electron, giving a net charge of -1. These two ions will "stick together" and together, they will have a net charge of 0, a very steady molecule. Many of these molecules will form what's known as a lattice structure, with each particle changing between sodium and chlorine in the lattice, giving a net charge of 0 across the entire structure. This is what is in your salt shaker.
Quote of the Day: "All of physics is either impossible or trivial. It is impossible until you understand it, and then it becomes trivial." -Ernest Rutherford [Source]
Keywords: Ion, Electrical, Charge, Sodium, Chloride, Salt
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