How does sunscreen block UV rays?

Question

How is it that a layer of cream can stop a particle that travelled from the sun, punched through 50 miles of atmosphere and still has enough energy to cause a burn?

Answer 1

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The principal ingredients in sunscreens are usually aromatic molecules conjugated with carbonyl groups. This general structure allows the molecule to absorb high-energy ultraviolet rays and release the energy as lower-energy rays, thereby preventing the skin-damaging ultraviolet rays from reaching the skin. So, upon exposure to UV light, most of the ingredients (with the notable exception of avobenzone) do not undergo significant chemical change, allowing these ingredients to retain the UV-absorbing potency without significant photo-degradation.[1]

Answer 2

before everything, there is not any UV molecule, because of the fact it somewhat is a ray (it somewhat is an element of the electro-magnetic spectrum) To the final of my awareness, sunscreen stops UV rays in 2 techniques, making use of two styles of energetic aspects. First: Inorganic aspects e.g. zinc oxide Are used to replicate or scatter ultraviolet (UV) radiation. 2d: organic and organic aspects (those would be the long and sophisticated sounding molecules on the decrease back of the bottle) those take up UV radiation, dissipating it as warmth. I assume it somewhat is finished ultimate with the aid of super organic and organic molecules, because of the fact they have many covalent bonds to take up the radiation.

Answer 3

It has strong Kung-Fu. Basically, its designed with the specific wavellengths of the ultraviolet light in mind. all you need is anything in the way that can absorb or reflect that particular energy of light. You can put a million bazillion miles of something that doesnt absorb it between and it will still pass through. The tiniest bit of something that does... and your golden and not all red and owies.

Answer 4

The cream is formulated with UV-absorbing compounds. These are usually molecules with one or more benzene rings (benzophenones, e.g.), whose absorption maxima are in the wavelength of interest. The energy is re-radiated at longer "nonburning" wavelengths.