Why do elements burn different colors




















Unfortunately, at the higher energy level, the electrons are unstable and will eventually fall to the lower energy level. When this happens, the energy which they absorbed has to be gotten rid of in some way. This means that the electrons eject a photon of energy equal to the energy difference between the two levels. Higher energy waves are more purplish, until they enter into ultraviolet and can't be seen by the naked eye and lower energy waves are red until you get low enough energy to enter into the infrared region.

The flame's colour changes due to the difference in the energy levels. Elements have set energy levels, so the only way you can get different colours is by using a different element in the flame, or by exciting the electrons to even higher energy levels. Unfortunately, the latter option is not really possible for you.

Most of the electrons will be just jumping up to the second energy level, whereas very few would be jumping higher, meaning that any different coloured photons will not be visible amongst the rest.

A few examples of these elements and colours are: Copper - blue-green, Potassium - lilac, Strongtium - red, Sodium - yellow like sodium street lamps! Sign up to join this community. The best answers are voted up and rise to the top. Stack Overflow for Teams — Collaborate and share knowledge with a private group.

Create a free Team What is Teams? Learn more. Why do some elements burn different colors? A sodium atom in an unexcited state has the structure 1s 2 2s 2 2p 6 3s 1 , but within the flame there will be all sorts of excited states of the electrons. Sodium's familiar bright orange-yellow flame color results from promoted electrons falling back from the 3p 1 level to their normal 3s 1 level.

The exact sizes of the possible jumps in energy terms vary from one metal to another. That means that each different metal will have a different pattern of spectral lines, and so a different flame color.

Flame colors are produced from the movement of the electrons in the metal ions present in the compounds. For example, a sodium ion in an unexcited state has the electron configuration 1s 2 2s 2 2p 6.

When heated, the electrons gain energy and can be excited into any of the empty higher-energy orbitals—7s, 6p, 4d, or any other, depending on the amount of energy a particular electron happens to absorb from the flame.

Because the electron is now at a higher and more energetically unstable level, it falls back down to the original level, but not necessarily in one transition. The electron transitions which produced lines in the visible spectrum involved atoms rather than ions. Jim Clark Chemguide.

Practical Details in Carrying out Flame Tests Clean a platinum or nichrome a nickel-chromium alloy wire by dipping it into concentrated hydrochloric acid and then holding it in a hot Bunsen flame. Repeat this until the wire produces no color in the flame. When the wire is clean, moisten it again in the acid and then dip it into a small amount of the solid to be tested so that some sticks to the wire. Place the wire back in the flame. Every element has its own characteristic set of energy levels.

Thus, an atom of Na has different energy levels and transitions than an atom of Li. The different mix of energy differences for each atom produces different colours. Each metal gives a characteristic flame emission spectrum. Check out these videos of flame tests Related questions What periodic table elements are radioactive? How can the periodic table be used to predict the properties of the elements? How can elements have different isotopes? How can elements be broken down?



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