Kristalisasi Eksotermik Natrium Asetat

Mengukur panas yang dilepaskan selama kristalisasi seketika

Thermochemistry Intermediate (High School) 30 menit ~$8,00

Tujuan

Kuantifikasi panas yang dilepaskan selama kristalisasi natrium asetat lewat jenuh menggunakan kalorimetri.

Latar Belakang

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.

Peringatan Keselamatan

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

APD yang Diperlukan

goggles

Bahan

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

Peralatan

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

Prosedur

1

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

8 menit Handle hot solution carefully
2

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

15 menit
3

Record the temperature of the supersaturated solution.

1 menit
4

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

3 menit
5

Record the maximum temperature reached.

1 menit
6

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

5 menit

Hasil yang Diharapkan

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.

Pembersihan

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

Detail

Kategori
Thermochemistry
Tingkat Kesulitan
Intermediate (High School)
Durasi
30 menit
Perkiraan Biaya
$8,00
Langkah
6
Bahan
2

Eksperimen Lainnya

Demonstrasi Reaksi Endotermik 20 min Entalpi Fusi Es 25 min Kalorimetri Cangkir Kopi 40 min Kapasitas Panas Spesifik Logam 40 min Kimia Kompres Dingin 20 min Panas Pembakaran Magnesium 50 min Pelarutan Tidak Selalu Eksotermik 25 min Simulasi Kalorimetri Bom 45 min Verifikasi Hukum Hess 60 min

Frequently Asked Questions

What is the objective of Kristalisasi Eksotermik Natrium Asetat?
Kuantifikasi panas yang dilepaskan selama kristalisasi natrium asetat lewat jenuh menggunakan kalorimetri.
How difficult is Kristalisasi Eksotermik Natrium Asetat?
This experiment is rated as Intermediate (High School). It takes approximately 30 minutes to complete.
What safety precautions are needed for Kristalisasi Eksotermik Natrium Asetat?
Key safety precautions include: Hot solution during preparation; Crystallization releases heat — container gets warm.
What materials are needed for Kristalisasi Eksotermik Natrium Asetat?
The main materials required are: Sodium acetate trihydrate, Distilled water.
What results should I expect from Kristalisasi Eksotermik Natrium Asetat?
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.