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__ Flame Tests Of Metal Cations __

**GPS : SC3-d, Students will relate light emission and the movement of the electrons to element identification.**

**Authors :** Michala Metcalf and Olenkeya Irvin **Abstract :** Perform flame tests of metal cations to observe their characteristic colors and match the colors observed to an appropriate wavelength of visible light.

** Method : **
 * Equipment : **
 * 6 Wooden Splints (pre-soaked in distilled water)
 * Wash Bottle
 * Bunsen Burner
 * 250 ml beaker
 * 400 ml beaker
 * Distilled water
 * Solid Salts**
 * LiCl
 * NaCl
 * KCl
 * CuCl2
 * BaCl2
 * CaCl2


 * Procedure : **
 * Gather all equipment and chemicals.
 * Set up lab space.
 * Pour Distilled water into the 250 ml beaker and pre-soak the 6 wooden splints.
 * Light your Bunsen burner, then adjust the flame to a moderate temperature (no yellow in the flame)
 * Begin by dipping the end of a water soaked splint into one of the solid compounds. The solid crystals should coat the end of the splint.
 * Hold the coated end of the splint in the central portion, but just to the side of it, of the Bunsen burner flame.
 * Record the dominant color observed and its associated wavelength.
 * Repeat instruction 5-7 for the other 5 solids.


 * **Dominant Color** || **Approximate Wavelength****(in NM)*** || **Compound** ||
 * ** Red ** || 701 || LiCl ||
 * ** Orange ** || 609 || CaCl2 ||
 * ** Orange-Yellow ** || 597 || NaCl2 ||
 * ** Yellow-Green ** || 577 || BaCl2 ||
 * ** Green-Blue ** || 492 || CuCl2 ||
 * ** Violet ** || 423 || KCl ||

**Formulas :** E = H x V (energy = plank's constant x frequency) H = 6.626 x 10 -34 V = C / **λ (** frequency = velocity / wavelength) C = 3.00 x 10 10 **nm = 10 -9m = 10 -7 m = 10 -5 cm**

**Calculations :** **LiCl -** V = (3.00 x 10 10) / (7.01 x 10 -5) = .42796 x 10 15 = 4.28 x 10 14

E = (6.626 x 10 -34) x (4.28 x 10 14) = 28.35928 x 10 -20 =2.84 x 10 -19

**CaCl2 -** V = (3.00 x 10 10) / ( 6.09 x 10 -5) = .4926108374 x 10 15 = 4.93 x 10 14

E= (6.626 x 10 -34) x (4.93 x 10 14) =32.66618 x 10 -20 = 3.27 x 10 -19

**NaCl2 -** V = (3.00 x 10 10) / (5.97 x 10-5) =.5025125628 x 10 15 = 5.03 x 10 14

E = (6.626 x 10 -34) x (5.03 x 10 14) = 33.32878 x 10 -20 = 3.33 x 10 -19

**BaCl2 -** V = (3.00 x 10 10) / (5.77 x 10 15) = .5199306759 x 10 15 = 5.20 x 19 14

E = (6.626 x 10 -34) x (5.20 x 19 14) = 34.4552 x 10 -20 = 3.45 x 10 -19

**CuCl -** V= (3.00 x 10 10) / (4.92 x 10 -5) = .6097560976 x 10 15 = 6.10 x 10 14

E = (6.626 x 10 -34) x (6.10 x 10 14) = 40.4186 x 10 -20 = 4.04 x 10 -19

**KCl -** V = (3.00 x 10 10) / (4.23 x 10 -5) = 12.69 x 10 15 = 1.27 x 10 14

E = (6.626 x 10 -34) x (1.27 x 10 14) = 8.41502 x 10 -20 = 8.42 x 10 -20

**Error Analysis :** There isn't a theoretical value to calculate the error.

**Conclusion :** Doing this lab let us find out the color and wave length the chemical produced. Each substances create a different level of energy produced. That means that every chemical will produce a different color in the flame test. The reason behind that would be because of the different energy levels. When an electron jump from one level to another and jump back; that shows the production of light.

**Safety Precautions :**
 * make sure hair is tied back
 * No jewelry
 * Closed toe shoes
 * Wear goggles
 * Wear aprons
 * Don't leave lab unattended