सोडियम एसीटेट का ऊष्माक्षेपी क्रिस्टलीकरण

तात्कालिक क्रिस्टलीकरण के दौरान निकलने वाली गर्मी को मापना

Thermochemistry Intermediate (High School) 30 मिनट ~$8.00

उद्देश्य

ऊष्मामिति का उपयोग करके अतिसंतृप्त सोडियम एसीटेट के क्रिस्टलीकरण के दौरान निकलने वाली गर्मी को मापें।

पृष्ठभूमि

When supersaturated sodium acetate crystallizes, it releases stored energy as heat. By triggering crystallization inside a calorimeter and measuring the temperature rise, the enthalpy of crystallization can be determined. This is the same principle used in reusable hand warmers.

सुरक्षा चेतावनियाँ

  • Hot solution during preparation
  • Crystallization releases heat — container gets warm

आवश्यक PPE

goggles

सामग्री

  • Sodium acetate trihydrate (80 g)
  • Distilled water (150 mL)

उपकरण

Polystyrene cup calorimeter Hot plate Thermometer Beaker (250 mL) Stirring rod

प्रक्रिया

1

Dissolve 80 g sodium acetate trihydrate in 20 mL water by heating to about 70°C. Stir until clear.

8 मिनट Handle hot solution carefully
2

Pour the solution into the polystyrene cup calorimeter. Allow to cool undisturbed to room temperature.

15 मिनट
3

Record the temperature of the supersaturated solution.

1 मिनट
4

Add a single small crystal of sodium acetate to trigger crystallization. Immediately stir gently and record temperature every 15 seconds.

3 मिनट
5

Record the maximum temperature reached.

1 मिनट
6

Calculate the heat released: q = mcΔT. Determine ΔH of crystallization per mole.

5 मिनट

अपेक्षित परिणाम

Temperature should rise 15-25°C above room temperature. The enthalpy of crystallization is approximately -19.7 kJ/mol for sodium acetate trihydrate. Measured values should be within 20% of this.

सफाई

The sodium acetate can be remelted and reused. Rinse the calorimeter. Non-toxic — can go down the drain.

Frequently Asked Questions

What is the objective of सोडियम एसीटेट का ऊष्माक्षेपी क्रिस्टलीकरण?
ऊष्मामिति का उपयोग करके अतिसंतृप्त सोडियम एसीटेट के क्रिस्टलीकरण के दौरान निकलने वाली गर्मी को मापें।
How difficult is सोडियम एसीटेट का ऊष्माक्षेपी क्रिस्टलीकरण?
This experiment is rated as Intermediate (High School). It takes approximately 30 minutes to complete.
What safety precautions are needed for सोडियम एसीटेट का ऊष्माक्षेपी क्रिस्टलीकरण?
Key safety precautions include: Hot solution during preparation; Crystallization releases heat — container gets warm.
What materials are needed for सोडियम एसीटेट का ऊष्माक्षेपी क्रिस्टलीकरण?
The main materials required are: Sodium acetate trihydrate, Distilled water.
What results should I expect from सोडियम एसीटेट का ऊष्माक्षेपी क्रिस्टलीकरण?
Temperature should rise 15-25°C above room temperature. The enthalpy of crystallization is approximately -19.7 kJ/mol for sodium acetate trihydrate. Measured values should be within 20% of this.