पादप वर्णकों का क्रोमैटोग्राफी

कागज क्रोमैटोग्राफी का उपयोग करके क्लोरोफिल और कैरोटेनॉयड को अलग करना

Qualitative Analysis Intermediate (High School) 60 मिनट ~$8.00

उद्देश्य

कागज क्रोमैटोग्राफी का उपयोग करके पादप वर्णकों को अलग करें और पहचानें, और प्रत्येक वर्णक के लिए Rf मान की गणना करें।

पृष्ठभूमि

Paper chromatography separates mixtures based on differential affinity for the stationary phase (paper) and mobile phase (solvent). Plant leaves contain multiple pigments: chlorophyll a (blue-green), chlorophyll b (yellow-green), xanthophylls (yellow), and carotenoids (orange). These pigments have different polarities, causing them to travel different distances up the paper as the solvent front advances.

सुरक्षा चेतावनियाँ

Acetone and petroleum ether are highly flammable — no open flames
Work in a well-ventilated area or fume hood
Avoid inhaling solvent vapors
Petroleum ether is a skin irritant

आवश्यक PPE

goggles gloves lab_coat

सामग्री

Fresh spinach leaves (5–10 leaves)
Or other dark green leaves
Acetone or isopropanol (50 mL)
Extraction solvent
Petroleum ether (30 mL)
Chromatography solvent
Chromatography paper (2 strips)
Whatman No. 1 or equivalent
Sand (1 teaspoon)
For grinding

उपकरण

Mortar and pestle Beaker (250 mL) with watch glass cover Pencil (not pen) Ruler Capillary tube Scissors

प्रक्रिया

Grind spinach leaves with a pinch of sand and 5 mL acetone in a mortar until a deep green extract forms.

5 मिनट Acetone is flammable

Draw a pencil line 2 cm from the bottom of the chromatography paper. Apply the extract using a capillary tube in a small spot. Let dry and reapply 3–4 times to concentrate.

10 मिनट

Pour petroleum ether into the beaker to a depth of about 1 cm. Suspend the paper strip so the origin line is just above the solvent level.

5 मिनट Work in fume hood

Cover the beaker with a watch glass and let the solvent rise by capillary action. Do not disturb until the solvent front is 1–2 cm from the top.

25 मिनट

Remove the paper, immediately mark the solvent front with pencil. Let dry completely.

5 मिनट

Identify the colored bands: carotenoids (orange, highest Rf), xanthophylls (yellow), chlorophyll a (blue-green), chlorophyll b (yellow-green, lowest Rf). Calculate Rf values for each band.

10 मिनट

अपेक्षित परिणाम

Four or more colored bands should be visible. Carotenoids (orange) travel farthest (Rf ≈ 0.9–0.95). Xanthophylls (yellow) at Rf ≈ 0.7. Chlorophyll a (blue-green) at Rf ≈ 0.5. Chlorophyll b (yellow-green) at Rf ≈ 0.4.

सफाई

Allow all solvents to evaporate in the fume hood. Dispose of paper in general waste. Clean mortar and pestle thoroughly.

विवरण

श्रेणी: Qualitative Analysis
कठिनाई: Intermediate (High School)
अवधि: 60 मिनट
अनुमानित लागत: $8.00
चरण: 6
सामग्री: 5

अधिक प्रयोग

pH संकेतक इंद्रधनुष 45 min अज्ञात पदार्थ पहचान चुनौती 75 min अवक्षेपण द्वारा धनायन पहचान 90 min ऋणायन पहचान परीक्षण 60 min कार्बोहाइड्रेट के लिए स्टार्च-आयोडीन परीक्षण 30 min ज्वाला उत्सर्जन स्पेक्ट्रोस्कोपी 60 min धातु आयनों के लिए बोरेक्स मोती परीक्षण 45 min साबुन विलयन के साथ कठोर जल परीक्षण 40 min हैलोजन के लिए बेल्स्टीन परीक्षण 25 min

Frequently Asked Questions

What is the objective of पादप वर्णकों का क्रोमैटोग्राफी?

How difficult is पादप वर्णकों का क्रोमैटोग्राफी?

This experiment is rated as Intermediate (High School). It takes approximately 60 minutes to complete.

What safety precautions are needed for पादप वर्णकों का क्रोमैटोग्राफी?

Key safety precautions include: Acetone and petroleum ether are highly flammable — no open flames; Work in a well-ventilated area or fume hood; Avoid inhaling solvent vapors.

What materials are needed for पादप वर्णकों का क्रोमैटोग्राफी?

The main materials required are: Fresh spinach leaves, Acetone or isopropanol, Petroleum ether, Chromatography paper, Sand.

What results should I expect from पादप वर्णकों का क्रोमैटोग्राफी?