![]() This demonstration can easily be used as a student lab.Soak wooden splints or cotton swabs in deionized water for a few hours and then dip them into small samples of each solid before putting them through the flame.If you cannot find wooden splints you can substitute generic cotton swabs, or longer craft swabs.Allow the splints to sit in the solutions overnight.Distribute the remaining wooden splints between the solutions.Use a separate wooden splint to stir each of the solutions.Note: if you do not have 100 mL beakers, substitute another piece of glassware and use a 50 mL graduated cylinder to add the deionized water.Add deionized water up to the 50 mL mark.7.9 grams of Strontium Chloride (SrCl 2).8.5 grams of Copper Chloride (CuCl 2*2H 2O).12.2 grams of Barium Chloride (BaCl 2*2H 2O) - Note: Barium chloride is highly toxic.Add the solid metallic salts to the beakers:.Label each of the 100 mL beakers with the name of the salt that it will hold.If you need to make ≈1.0M solutions of the metallic salts follow these instructions: Read a Safety Alert from the American Chemical Society about the traditional procedure for this demonstration.The American Chemical Society Committee on Chemical Safety recommends that this method be discontinued immediately. The traditional Rainbow Demonstration required that a highly flammable solvent, such as methanol or ethanol, be mixed with the metallic salts. This procedure is an updated version of the traditional one.The purpose is to demonstrate to students the variety of colors produced when different metals or metallic salts meet a flame. The Rainbow Demonstration (or Rainbow Flame Demonstration) is an activity popularly conducted in chemistry classrooms.Wash hands after handling materials used to prepare for or perform this experiment.Do not reach over it, tie back hair, and secure loose clothing. Keep flames away from flammable substances. ![]() Always use caution around open flames.Wear proper personal protective equipment when preparing and working with solutions.Safety goggles and lab apron are required. Students should wear proper safety gear during chemistry demonstrations.250 mL beaker or plastic or cardboard cup half full of waterĬopies of the visible light spectrum chart showing wavelength and frequency values.50 mL of 1.0M Strontium Chloride (SrCl 2).50 mL of 1.0M Calcium Chloride (CaCl 2).50 mL of 1.0M Barium Chloride (BaCl 2) - Note: Barium chloride is highly toxic.Wooden splints (number depends upon how many times the demo will be performed).Teacher Preparation: 30 minutes, longer if solution preparation is necessary This lesson supports students’ understanding of Identify an unknown metal by the color it emits when passed through a flame.Calculate the wavelength of light given its frequency.Calculate the frequency of light given its wavelength.Use flame tests to identify a metal or metallic salt by the color that it produces when it is put into a flame.HS-PS4-3: Evaluate the claims, evidence, and reasoning behind the idea that electromagnetic radiation can be described either by a wave model or a particle model, and that for some situations one model is more useful than the other.īy the end of this demonstration, students should be able to.HS-PS4-1: Use mathematical representations to describe a simple model for waves that includes how the amplitude of a wave is related to the energy in a wave.This activity will help prepare your students to meet the performance expectations in the following standards: In this demonstration, students will observe the variety of colors produced when different metals or metallic salts are heated in a flame.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |