|This is the talk page for discussing improvements to the Flame test article.|
|WikiProject Chemistry||(Rated Start-class, Low-importance)|
- 1 People asking us to do their homework for them instead of reading the article
- 2 Structure suggestion
- 3 restored
- 4 Ions only?
- 5 Test Description
- 6 Periodic table?
- 7 Pictures
- 8 Suspected vandalism?
- 9 Magnesium
- 10 Mislabeling
- 11 Agree need pictures
- 12 Blatant inconsistency
- 13 Flame test? Materials? WHERE TO GET THEM?
People asking us to do their homework for them instead of reading the article
what is the main reason for carrying out a flame test? --18.104.22.168 09:15, 8 December 2005 (UTC)
What are the inaccuracies involved in using flame tests for identification purposes? Your little chemist—The preceding unsigned comment was added by 22.214.171.124 (talk • contribs) 18:40, November 16, 2005 (UTC)
It can help Idenify elements in a compound. It's quick and easy. The main inaacuracies are the fcat that the colours can be similar between two elements, one may mask another, to be able to see the colours some times you need large amounts of the element in the compuund --Wolfmankurd 12:17, 8 June 2006 (UTC)
Should probably be documented in the article anyways:
- The flame test is a fast, simple and easy way to detect (qualitatively) certain elements in a sample.
- It only works with certain elements (generally metals)
- The test depends on the ability of the chemist to recognize the color of an element (and some are similar, also forget it if you are color blind).
- The element must be present in fairly large concentrations
- The presence of an element can be masked by another element (hence the cobalt glass filter which is used, for instance, to detect other elements in the presence of sodium which would normally overwhelm the light).
I'll see about neatening this up and adding it to the article at some point. RJFJR 20:16, 8 December 2005 (UTC)
anon 126.96.36.199 removed the common metals section including the pictures. I don't know if it was on purpose. I restored it. RJFJR 18:45, 28 January 2006 (UTC)
I thought that the flame test could only be carried out on metallic cations, not normal elements. I was going to edit references to "metals" to "Metallic Ions" but I wanted to check with the communitity beforehand. 188.8.131.52 09:11, 28 May 2006 (UTC)
Also, an explaination of the chemical side of the test should be added; that the reason for the emittion of light is caused by electrons in the element being given energy from the flame, raising the electrons to a set higher energy level, and by returning from the higher energy level to the original energy level, the extra energy is given off as electron-magnetic radition, causing the change of colour in the flame by radiation in the light spectrum. (general explaination, needs a lot of work) 184.108.40.206 09:31, 28 May 2006 (UTC)
add, the fact that the colour of the wave depends on energy of the photon it's wavelength/frequency, depends on the size of the jump made by the electron, depends on the element --Wolfmankurd 12:14, 8 June 2006 (UTC)
Rifleman 82 has introduced a section 'Test' to replace a section removed by me for WP:NOT violations. I believe that this section (as well as the one I removed) is redundant, and doesn't add to the article - I believe that enough information is conveyed in this sentence from the first paragraph:
It involves introducing a sample to a flame, and observing the colour that results. Samples are often held on the looped end of a clean, nonreactive wire or on the tip of a wood stirring stick soaked in water.
This new section can also be read as directly contradicting the previous paragraph - 'does not require any special equipment' could be either:
- No equipment is needed that isnt normally found in a chem lab ; or
- Is doable with equipment a lay person could have
I think the second definition is what most people are likely to read it as (and, it is reasonably true for the flame test - a match will do the job well enough), and that would make a bunsen certainly 'special equipment', and probably platinum wires and HCl, too. LVC 01:13, 29 January 2007 (UTC)
If you're a chemist, a bunsen burner and platinum wire will not be "special equipment". A match or a wooden stick will probably give you a lot of problems from sodium contamination. I didn't catch the part on the top, I've tweaked it again. --Rifleman 82 04:22, 29 January 2007 (UTC)
Would it add to the table to include the column in the periodic table? I'd imagine that relates to the emission color. —Ben FrantzDale 00:54, 13 November 2007 (UTC)
This article really needs pictures of the diffrent tests. One persons mauve is anothers violet so the description can be a bit accurate. Even an emmision spectrum could help. Could someone think about this because i just dont have the time? —Preceding unsigned comment added by 220.127.116.11 (talk) 09:24, 18 February 2008 (UTC)
I've cut Also, when most of the chemicals are put in rubbing oil it makes a darker light. which looked suspiciously nonsensical to me (and I'm shocked that it'd been on the page since 18 September 2008, surviving many edits). It was added by User:Jordaniswoo, whose few edits all seem to have been vandalism, so I feel fairly confident that it's trash: if anyone knows better, feel free, as always, to revert! Kay Dekker (talk) 15:20, 19 May 2009 (UTC)
I swear I've change this one before. Magnesium ions do not give a colour with a flame test. The photon of light produced is outside the visible spectrum. For some reason it keeps being put in here as "bright white". Magnesium metal does burn with a bright white flame, but a flame test onm a magnesium salt does NOT give any colour, least of all a "bright" one. Fork me (talk) 10:02, 27 January 2011 (UTC)
Agree need pictures
The colors listed seem to be incorrect at least for common ions. Calcium is listed as "brick red" yet I (as Lab TA) see it as orange and CRC Handbook lists it as orange-red (Calcium emission lines extend into yellow, our lab analyzed Calcium in Concrete using an AA and some Calcium lines are close to Sodium D lines at 589 nm). Perhaps this is through Cobalt glass? That should be noted.
Pyrotechnic colorant lists Calcium as Orange: lines at "most intense: 591–599 nm and 603–608 nm".
I worked for a demolitions company that also put on fireworks shows. Barium is not pale green and Boron is not dark green, those are reversed. Looking at emission lines of these metals/metalloids in CRC Handbook or Perkins Elmer Atomic Absorbtion instrument manual or specific Hollow Cathode Lamp emission lines list (absorption lines are complementary to emission lines) or Astronomical emission line list that these are incorrect. Note that AA Instruments can be operated in emission as well as absorption modes.
There was a confusion with source material. Flame emission requires a volatile (stable) sample. A metal salt solution is generally used. (I change references from "Sodium metal" and "Calcium metal" in another article.) Although Copper wire oxidizes in a flame and the relatively volatile Copper(I) Oxide provides some color, the more volatile Copper(I)Chloride creates a stronger color. (See reference to Scientific American article on creating a Copper Laser for high temperature stability of Copper(I)Chloride.) Boron salts (e.g. Boric Acid) are a weak green unless wetted with alcohol which forms the more volatile alcoholates (B(MeO)3). I'd note that Strontium Nitrate is the Colorant used in road flares (containing Strontium Nitrate and Magnesium metal).
Although Flame test may be done in any flame, luminous flames (e.g. containing significant carbon) cause interference. Flame tests are also affected by flame temperature (Adiabatic flame temperature)
The table says the flame for Zinc is colourless, but the picture beside it suggests otherwise. What colour is blue? — Preceding unsigned comment added by 18.104.22.168 (talk) 13:21, 5 December 2012 (UTC)
Flame test? Materials? WHERE TO GET THEM?
hey guys i am a junior at a Waldorf school in Cali and im performing a flame test tomorrow. i need to know where to buy the different materials for different colored flames and how to acquire them. PLEASE HELP! — Preceding unsigned comment added by 22.214.171.124 (talk) 19:47, 4 June 2014 (UTC)