# flame test of metal cations

To relate these results to the types of electronic transitions occurring in these elements. Primarily, the flame test detects the presence of metalions in a compound, and as ions of each element have a specific characteristicbased in their emission spectrum, the flame test for every element is differentand distinctive. The characteristic colors observed are due to emitted electromagnetic radiation from the excited metal cations. 8: Flame Tests of Metal Cations (Experiment), [ "article:topic", "electromagnetic radiation", "authorname:smu", "Flame Tests", "showtoc:no", "license:ccbync" ], https://chem.libretexts.org/@app/auth/2/login?returnto=https%3A%2F%2Fchem.libretexts.org%2FBookshelves%2FAncillary_Materials%2FLaboratory_Experiments%2FWet_Lab_Experiments%2FGeneral_Chemistry_Labs%2FOnline_Chemistry_Lab_Manual%2FChem_10_Experiments%2F08%253A_Flame_Tests_of_Metal_Cations_(Experiment). They are more useful for some metals than others; particularly for the Group 1 metals, they provide a good way of quickly identifying the metal ion present. In this lab, how do the metal cations become "excited"? Flame Tests of Metal Cations Experimental Data and Observations Solution Dominant Flame Color Wavelength (nm) LiCl NaCl KCl CuCl2 BaCl2 CaCl2 Data Analysis Using the wavelengths recorded above, calculate the corresponding frequencies and photon energies for the emitted radiation observed for each compound tested. Objectives. To practice writing electron configurations for these (and other) elements. Check with your syllabus to find which tests you will need to know for the examination. Record the results of your calculations in the table below. Circle the correct responses to complete the following statement: EM radiation is emitted when electrons make transitions from low / high to low … Test the different metal salt solutions in a hot flame and observe the characteristic color given off by each excited atom and to identify the metal ion present in one unknown metal salt solution Flame test colors of alkali metal cations. The purpose of this experiment is to learn the techniques to separate and identify some common cations and to understand the principles for the equilibria of precipitation and complex formation. Well, when an atom (or ion) absorbs energy, its electrons can make transitions from lower energy levels to higher energy levels. Differences in the wavelengths of visible light are manifested as different colors, shown in the Color Spectrum below (colors can be seen in the PDF document on-line). The emitted photons that give rise to this color have energies of $$4.405 \times 10^{-19} J$$. Select one. The flame test is generally used when testing alkali metals, while transition metals form differing precipitations when a … The flame test is an analytical chemistry method used to help identify metal ions. A common test to distinguish group 1 and group 2 ions is the flame test, where the metal compound or its solution is heated in a roaring blue Bunsen flame. The following table shows the flame tests for metal ions (cations): Lithium - Crimson, Sodium - Yellow, Potassium - Lilac, Calcium - Red, Copper(II) - blue-green. In this lab, you will perform flame tests of several different metal cations. AimTheoryMaterials RequiredProcedureObservation and InferenceResultsPrecautionsFrequently Asked Questions on Systematic Analysis of Cations Analysis of metallic elements in compounds or samples is an integral part of chemical research. The result is called a line emission spectrum, and can serve as a ‘fingerprint’ of the element to which the atoms belong. 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