My year 5 class want to know why colours fade when left in sunlight. can anyone give a simple explanation?
2007-02-13 23:58:30 · 7 answers · asked by Anonymous in Science & Mathematics ➔ Physics
Ultraviolet light waves have more energy than visible light waves, because they are higher frequency. This energy causes pigment molecules to break down, which makes colours fade.
2007-02-14 00:05:42 · answer #1 · answered by poorcocoboiboi 6 · 2⤊ 0⤋
UV light has enough energy to ionise molecules in the pigments. Oxygen in the atmosphere will most readily react with the ionised pigment. It's reactive and it's so readily available.
For reasons of chemistry which I don't understand, many oxides tend to be white. I've never had a reasonable explanation as to why.
The upshot of it all is that UV light will slowly bleach colours, even in your hair.
2007-02-14 10:10:31 · answer #2 · answered by BIMS Lewis 2 · 0⤊ 0⤋
The 1st answer given is technically correct.
UV has more energy than visible wavelengths of light from the atomic equation E = h f (Energy = Planck Constant x Frequency)
You will find that black clothes fade faster than lighter colours, due to black absorbing more of the 'photons' of light and heat. White clothes tend to reflect alot more photons and heat.
2007-02-14 00:11:44 · answer #3 · answered by Doctor Q 6 · 0⤊ 0⤋
sunlight bleaches colours. the only things that can withstand the sunshine are specially treated photographs such as lithium prints, and certain Kodak emuslions... everything else fades.
2007-02-14 00:08:40 · answer #4 · answered by Anonymous · 0⤊ 0⤋
It physically 'knocks' electrons out of the atoms in the dye molecules causing their chemical properties to change and hence they break down into non-coloured compounds.
2007-02-14 00:08:33 · answer #5 · answered by Timbo 3 · 0⤊ 0⤋
ugh i searched and googled and asked for some miracle shampoo which could get crimson dye out of my hair whilst i attempted to dye it, got here out incredibly blotchy AND with warm roots. seems you need to use head and shoulders, supposedly it enables fade the colour, yet whilst the dye grew to become into everlasting (as i'm assuming that's) it is not going to easily get out of your hair and depart it your organic shade - it is gonna fade and grow to be a brassy orange. i'd say you are able to bleach it amazing now, you're gonna harm it besides, so why wait till it grows out? whether it comes out orangey, you need to use a toner... yet you may probable flow to a salon to bleach it, it is slightly volatile. sturdy success! playstation i've got desided to easily permit my hair enhance in and out no way dye it back... properly... no longer for a mutually as a minimum of.
2016-10-02 03:04:56 · answer #6 · answered by alarid 4 · 0⤊ 0⤋
tell them that sunlight is like an eraser (rubber) and the more you use it, the more it rubs out
2007-02-14 00:15:57 · answer #7 · answered by jamus d woespuss 4 · 0⤊ 0⤋