ल्यूमिनॉल के साथ केमिल्यूमिनेसेंस

बिना गर्मी के रासायनिक अभिक्रिया के माध्यम से नीली रोशनी उत्पन्न करना

Classroom Demonstrations Intermediate (High School) 30 मिनट ~$15.00

उद्देश्य

उत्प्रेरक की उपस्थिति में हाइड्रोजन पेरॉक्साइड के साथ ल्यूमिनॉल को ऑक्सीकृत करके रासायनिक प्रतिदीप्ति प्रदर्शित करें, दृश्यमान नीली रोशनी उत्पन्न करें।

पृष्ठभूमि

Luminol (3-aminophthalhydrazide) produces an eerie blue glow when oxidized by hydrogen peroxide in basic solution with a transition metal catalyst. The oxidation produces 3-aminophthalate in an excited electronic state, which releases energy as a photon of blue light (425 nm) as it returns to the ground state. This is the same reaction used by forensic scientists to detect trace amounts of blood at crime scenes, where the iron in hemoglobin acts as the catalyst.

सुरक्षा चेतावनियाँ

  • NaOH is corrosive — handle with care
  • Potassium ferricyanide is harmful if ingested
  • Perform in a dark room for best effect
  • Do not mix stock solutions until ready to demonstrate

आवश्यक PPE

goggles gloves lab_coat

सामग्री

  • Luminol (0.5 g)
    3-aminophthalhydrazide
  • Sodium hydroxide (NaOH) (5 g)
    To make solution basic
  • Hydrogen peroxide (3%) (50 mL)
    Household concentration
  • Potassium ferricyanide (K₃[Fe(CN)₆]) (0.5 g)
    Catalyst
  • Distilled water (500 mL)

उपकरण

Beakers (500 mL, 2) Spiral glass tubing or clear tubing Dark room or blackout curtains Magnetic stirrer (optional)

प्रक्रिया

1

Prepare Solution A: Dissolve 0.5 g luminol and 5 g NaOH in 250 mL distilled water.

5 मिनट NaOH is corrosive
2

Prepare Solution B: Dissolve 0.5 g K₃[Fe(CN)₆] in 250 mL of 3% H₂O₂.

5 मिनट
3

Darken the room completely. Allow eyes to adjust for 1–2 minutes.

2 मिनट
4

Pour both solutions simultaneously into a large beaker or through spiral glass tubing. A bright blue glow appears immediately.

3 मिनट
5

Observe the glow lasting for several minutes. Stirring or agitation renews the glow by mixing fresh reactants.

10 मिनट
6

Discuss the mechanism: luminol oxidation → excited 3-aminophthalate → photon emission (425 nm). Compare with bioluminescence and fluorescence.

5 मिनट

अपेक्षित परिणाम

A vivid blue glow appears when the solutions are mixed. The light intensity peaks immediately and fades over several minutes. The glow is bright enough to read by in a completely dark room.

सफाई

The spent solution is relatively non-toxic. Pour down the drain with copious water. Rinse all glassware.

विवरण

श्रेणी
Classroom Demonstrations
कठिनाई
Intermediate (High School)
अवधि
30 मिनट
अनुमानित लागत
$15.00
चरण
6
सामग्री
5

अधिक प्रयोग

आयोडीन घड़ी अभिक्रिया 45 min गायब होता बीकर (अपवर्तनांक मिलान) 15 min गैर-न्यूटोनियन तरल: ऊब्लेक 20 min घनत्व स्तंभ इंद्रधनुष 30 min तात्कालिक ठंड: अतिशीतित जल 120 min थर्माइट अभिक्रिया 30 min दोलनशील ब्रिग्स-राउशर अभिक्रिया 40 min सूखी बर्फ में मैग्नीशियम जलाना 25 min सोडियम और पानी की अभिक्रिया 25 min हाथी टूथपेस्ट 20 min

Frequently Asked Questions

What is the objective of ल्यूमिनॉल के साथ केमिल्यूमिनेसेंस?
उत्प्रेरक की उपस्थिति में हाइड्रोजन पेरॉक्साइड के साथ ल्यूमिनॉल को ऑक्सीकृत करके रासायनिक प्रतिदीप्ति प्रदर्शित करें, दृश्यमान नीली रोशनी उत्पन्न करें।
How difficult is ल्यूमिनॉल के साथ केमिल्यूमिनेसेंस?
This experiment is rated as Intermediate (High School). It takes approximately 30 minutes to complete.
What safety precautions are needed for ल्यूमिनॉल के साथ केमिल्यूमिनेसेंस?
Key safety precautions include: NaOH is corrosive — handle with care; Potassium ferricyanide is harmful if ingested; Perform in a dark room for best effect.
What materials are needed for ल्यूमिनॉल के साथ केमिल्यूमिनेसेंस?
The main materials required are: Luminol, Sodium hydroxide (NaOH), Hydrogen peroxide (3%), Potassium ferricyanide (K₃[Fe(CN)₆]), Distilled water.
What results should I expect from ल्यूमिनॉल के साथ केमिल्यूमिनेसेंस?
A vivid blue glow appears when the solutions are mixed. The light intensity peaks immediately and fades over several minutes. The glow is bright enough to read by in a completely dark room.