<p>Lab Group Members: </p><p>Flame Tests of Metal Ions -- Chemistry Laboratory</p><p>Purpose: To discover the different frequencies of light that is emitted by various metallic ions.</p><p>Pre Lab Questions:</p><p>1. Define atomic emission spectrum.</p><p>2. Define ground state</p><p>3. Define Photon</p><p>4. How can electrons become excited?</p><p>5. What generally happens when electrons loose extra energy?</p><p>Background information:</p><p>Using your text book include information about the electromagnetic spectrum. Make sure to include information about the color of light in the visible spectrum and the energy of the light.</p><p>Safety: </p><p> Follow appropriate safety procedures when operating the burners. Tie back long hair and secure loose clothing.</p><p> Wear safety googles at ALL TIMES. </p><p> Many of the salts used in this experiment are toxic. Be sure to wash hands thoroughly after coming into contact with any of the substances.</p><p>Materials</p><p>Potential Metal Salts Equipment  Sodium nitrate  Bunsen Burner  Calcium chloride  Striker  Strontium chloride  q-tip  Barium nitrate  Lithium chloride  Copper II chloride  Magnesium chloride  Potassium nitride Procedure:</p><p>1. If the burner is not lit, follow the appropriate procedures for lighting the burner. DO NOT leave lit burner unattended! 2. Dip the popsicle stick in the beaker of water and salt. </p><p>3. Place the popsicle stick into the burner flame. </p><p>4. Observe the color produced and record it in a table you construct. Watch carefully because some colors will not last long. Be as descriptive as possible. (e.g. red orange instead of orange)</p><p>5. Repeat steps 1-4 until you have observed all the metal salts and the unknown.</p><p>Observations:</p><p>Metal Lithium Calciu Copper Sodiu Strontiu Barium ion m m m</p><p>Flame Color</p><p>Unknown </p><p>Flame Color</p><p>Metals Presen t</p><p>Post Lab Questions:</p><p>1. Explain how colors are produced by the metal ions. Include terms such as ground state, excited state and photon in your explanation. </p><p>2. Explain how a forensic scientist could use similar methods to determine an unknown substance at a crime scene. </p><p>3. List the electron configurations for the metal elements used in the compounds you tests. You may use the noble gas configurations if you would like. 4. Based on your observations what are the metal ions present in the unknown sample?</p>