Question

CHEMICALS AND EQUIPMENT Bunsen burner Striker or matches Wire loops -10 mL of 1 M NaCl -10 mL of 1 M KI -10 mL of 1 M Nal -10 mL of 1 M KCI -10 mL of 1 M CaCl, -10 mL of 1 M CuSO -10 mL of 1 M BaCl . -10 mL of 1 M Borax Safety Concerns Always wear safety goggles. Keep your hand away from the flame by holding the bottom of the wire loop EXPERIMENTAL PROCEDURE Dip the end of a wire loop into one of the eight solutions 1. 2. Hold the wire loop next to the Bunsen burner flame so that the wet end just touches the flame. Fiqure 9.3. While performing the flame test, keep your hand below the flame to avoid burning yourself! After a few seconds, the characteristic color from the test solution will appear in the flame. 3. 4. Repeat for each of the known solutions 5. Construct a data table; identify which element can be identified by its character- istic color. CLEANUP AND DISPOSAL Dispose of the leftover solutions in the appropriate containers in your laboratory. INFORMATION FOR INSTRUCTORS 1 M NaCl: add 14.6 g NaCI to 250 mL of distilled or deionized water 1M KI: add 415 g KI to 250 mL of distilled or deionized water 1 M Nal: add 37.5 g Nal 250 mL of distilled or deionized water to 1 M KCl: add 18.6 g KCl to 250 mL of distilled or deionized water 1 M CACL; add 35.2 g CaCl, to 250 mL of distilled or deionized water 1 M CUSO add 40 g CuSO to 250 mL of distilled or deionized water 250 mL of distilled or deionized 1 M BaCl add 52 g BaCl to water add 95.3g Borax (sodium tetraborate decahydrate, Na,B,O,-10H,O) to 250 mL of distilled or deionized water 1M Borax: Date Section DATA AND OBSERVATIONS Data Table Element Responsible Species Color Observed 1. What conclusions can you make about flame color and the elements in a solution? Which elements are responsible for the different colors you observed? 2. If you saw a blue flame, would that have more energy than a yellow flame? 3. What color would you expect chloride and copper sulfate? 4. to see in a flame test for a solution made by combining sodium

Answer 1

SPECIES	COLOR OBSERVED	ELEMENT RESPONSIBLE
NaCl	Orange Yellow	Sodium ions
KI	Violet	Potassium ions
KCl	Violet	Potassium ions
NaI	Bright Orange	Sodium ions
CaCl2	Deep Orange	Calcium(+2) ions
CuSO4	Light green	Copper (+2) ions
BaCl2	Yellow - green	Barium (+2) ions
Borax	Apple green	Sodium Borate

Q.1 Flame color represents the different kind of cations present in the element. The color will be lower in energy which is emitted from the smaller atoms. When the electrons experience the flame or in other words known as thermal energy, electron gets excited to higher energy levels and when it again comes back to the ground state , it emits radiation.

Q.2 The elements which are responsible for the different color is mostly the cation. The prominent color is that of the cation .

Q.3 Blue flame will definitely have more energy than the yellow flame because the yellow flame has higher wavelength than the blue flame because of the fact that the energy is inversly proportional to the wavelength.

Q.4 Sodium Chloride and Copper sulfate when mixed and performed flame test , Orange -green color will be produced.