Flame On Test Chart printable pdf download

Name _____________________________

Date ___________

Flame

On!!

Background:

The normal electron configuration of atoms or ions of an element is known as the “ground state.” In this

most stable energy state, all electrons are in the lowest energy levels available. When atoms or ions in the “ground

state” are heated to high temperatures, some electrons may absorb enough energy to allow them to “jump” to higher

energy levels. The element is then said to be in the “excited state.” This excited configuration is unstable, and the

electrons “fall” back to their normal positions of lower energy (ground state). As the electrons return to their normal

levels, the energy that was absorbed is emitted in the form of visible light. The color of this light can be used as a

means of identifying the elements involved. Such analysis is known as a flame test.

To do a flame test on a metallic element, the metal is first dissolved in a solution and the solution is then

held in the hot, blue flame of a Bunsen burner. This test works well for metal ions, and was perfected by Robert

Bunsen (1811 – 1899). Many metallic ions exhibit characteristic colors when vaporized in the burner flame.

The wooden splints have been soaking overnight and the metal solutions have been dried onto them. When

using a splint, one must be careful to wave the splint through the flame rather than holding it in the flame for

extended periods, to avoid setting the splint itself on fire.

To relate this lab activity to real-life – fireworks come to mind. A pyrotechnic colorant is a chemical

compound which causes a flame to burn with a particular color. These are used to create the colors in pyrotechnic

compositions like fireworks and colored fires.

Purpose:

The purpose is to observe the characteristic colors produced by certain metallic ions when

vaporized in a flame and then to identify an unknown metallic ion by means of its flame test.

Materials:

Set of metal chloride solutions (NaCl, KCl, CaCl

, SrCl

, LiCl, BaCl

)

Burner

Wood splints

Safety Glasses

Flint Spark Torch Igniter

Colored Pencils

Flame On Test Chart