So, a lot of my physics project actually has to do with chemistry, so here's some of the background information from my great information source that I use to help me through:
Source: http://stars.astro.illinois.edu/sow/spectra.html
Photons and Energy:
Though light and its partners can act like waves, at the same time they can act like a stream of particles. In a crude sense, these particles, called "photons," carry the waves. The smaller the wavelength of the photon the more energy it carries, that is, the greater the ability of the photon to act on some physical substance. For example, the energy of infrared is registered as heat, ultraviolet light (the sun) can burn and an X-ray can also cause damage with too much exposure.
Electromagnetic Waves:
Except for the energy they carry, all portions of the spectrum -- ordinary light, infrared, radio, ultraviolet -- are fundamentally the same. They are unified by thinking of them as "electromagnetic waves," waves of alternating strength in electric and magnetic fields that all move through space at the "speed of light" (called "c") of 300,000 kilometers per second (186,000 miles per second). The differing kinds of radiation simply have different wavelengths, (that is, the separations between crests in two successive waves).
Visual radiation is in the middle, with wavelengths that extend from 0.00004 centimeters for violet light to about 0.00007 centimeters for extreme red. These wavelengths are so short that astronomers use a small unit of distance, the "Angstrom" (A), which is 0.00000001 centimeters long. The violet limit therefore falls at 4000 A and the red limit near 7000 A or a bit longer. Infrared runs from the red limit to about 0.1 millimeter, and the radio to as long as you wish, even to kilometers. Ultraviolet runs from 4000 A down to about 100 A, X- rays take over to about 1 A, and these are followed by the gamma rays to no known lower limit. The named divisions are artificial and serve only to block out large spectral segments.
Molecules:
The electrons of two or more atoms can link together to form chemical bonds that make molecules from the chemical elements. The atoms can be the same or can be different.The molecules have characteristics that are completely different from their component atoms. There is no limit on the number of atoms that can be linked, and as a result there is an infinite number of kinds of molecules, the collection of which gives us all the riches of the natural world, including life.
A common example of a "chemical compound" is molecular oxygen (two oxygen atoms locked together) or water (two hydrogen atoms coupled with an oxygen atom).
Ions:
A normal atom, with equal numbers of protons and electrons, is electrically neutral. You get no electric shock by touching matter in its normal state. It is easy, however, to remove electrons from an atom and to electrically unbalance it. The result of electron removal is a positively charged "ion."
Isotopes:
The number of neutrons present in any kind of atomic nucleus is not fixed. All atoms have a set of variants called "isotopes" in which the proton number is the same but the neutron number is different. For example, the most common kind of hydrogen has only one proton. But you can attach a neutron to the proton and still have hydrogen. This heavy form, called "deuterium," is present in nature.
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