S: Gabriela Romero
BC: By: Gabriela Romero March-09-2012
FC: Energy | of | Electrons
1: Introduction | The electromagnetic spectrum is the range of all possible frequencies of electromagnetic radiation. | The electromagnetic spectrum extends from low frequencies used for modern radio communication to gamma radiation at the short-wavelength (high-frequency) end, thereby covering wavelengths from thousands of kilometers down to a fraction of the size of an atom
2: Goals | 1. Observe how a simple diffraction grating spectroscope operates. | 2. Observe and draw the spectra of several elements.
3: Materials | 1. Busen burner. 2. Chloride salt of lithium, potassium, strontium, calcium, and cooper (II). 3. Color pencils 4. Diffraction grating spectroscope. 5. Incandescent light. 6. Precooked wooden splints.
4: Procedure | 1. Observe continuous spectrum by looking at an incandescent light with your spectrometer. Note the calibration marks along the bottom of the box for lithium chloride in the data section. | 2. light your Bunsen burner. Adjust the burner until it produces a blue colorless flame. | 3. Dip a Presoaks splint into the lithium chloride.
5: 4. have your lab partner look through the spectrometer at the flame.Put the tip of the splint in the flame long enough for the salt to burn. | 5. Sketch the spectrum at the appropriate calibration marks. Label or color the bright lines to identify them. | 6. Repeat step 3-5 for the remaining known salts and an unknown salt, using a new splint for each test.
6: Data | 1. Lithium Chloride | 2. Potassium Chloride | 3. Strontium Chloride
7: 4. Sodium Chloride | 5. Cooper Chloride | 6. Unknown Salt
8: Analysis | 1. Since each element produces a characteristic spectrum, what can you conclude about the location of the electrons? | A: We can see how atoms valance electrons to become "Exited" | 2. If you have observed only the color of the flame as the salt burned, you would have conducted a flame test. Would you say that a flame test or a spectroscopic test is more accurate? Why? | A: Aflame test is not very accurate because the other salts that you were looking will fall into the Bunsen burner creating a bad flame.
9: 3. Suppose that you had used the same wooden splint to burn all the salts in the flame. What difficulty could this have introduced? | A: The salt was burned and the splint affected the color flame of the salt. | 4. Helium was discovered in the sun before it was discovered on the earth. How could this be. | A: Because it has a very low density and it was not found combined with other elements in both location Earth & Sea. - Helium is more abundant in the sun. | 5. What was the identity of your unknown salt? | A: Salt??? I don't emender xD