Spezifische Wärmekapazität von Metallen

Vergleich der Wärmekapazitäten von Aluminium, Kupfer und Eisen

Thermochemistry Intermediate (High School) 40 Min. ~$10,00

Ziel

Die spezifische Wärmekapazität mehrerer Metalle mithilfe der Mischungsmethode bestimmen und mit Literaturwerten vergleichen.

Hintergrund

The specific heat capacity of a metal can be determined by heating a known mass of metal to a known temperature, then transferring it to water in a calorimeter and measuring the temperature change. Energy conservation (q_metal = -q_water) allows calculation of the metal's specific heat.

Sicherheitswarnungen

  • Hot metals and boiling water — burn risk
  • Use tongs to transfer hot metals
  • Do not touch hot metals with bare hands

Erforderliche PSA

goggles lab_coat

Materialien

  • Metal samples (Al, Cu, Fe) (50 g each)
    Cylindrical pieces work best
  • Distilled water (300 mL)
  • Boiling water (500 mL)
    For heating metals

Ausrüstung

Polystyrene cup calorimeter Beaker (600 mL) Hot plate Thermometer (2) Analytical balance Tongs String

Durchführung

1

Weigh each metal sample accurately. Record masses.

3 Min.
2

Place all metals in boiling water for 10 minutes to reach 100°C.

12 Min. Handle hot water carefully
3

Add 100 mL room-temperature water to the calorimeter. Record initial temperature.

2 Min.
4

Using tongs, quickly transfer the aluminum sample to the calorimeter. Stir and record max temperature.

5 Min. Hot metal — use tongs
5

Calculate c(Al) = m(water)×c(water)×ΔT(water) / [m(Al)×ΔT(Al)].

5 Min.
6

Repeat steps 3-5 for copper and iron.

15 Min.
7

Compare measured values with accepted: Al=0.897, Cu=0.385, Fe=0.449 J/g°C.

5 Min.

Erwartete Ergebnisse

Aluminum should give the largest temperature rise in the water (highest specific heat), followed by iron, then copper. Measured values should be within 10-20% of accepted values.

Aufräumen

Allow metals to cool completely. Dry and store. Pour water down the drain. Clean calorimeter.

Details

Kategorie
Thermochemistry
Schwierigkeit
Intermediate (High School)
Dauer
40 Min.
Geschätzte Kosten
$10,00
Schritte
7
Materialien
3

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Frequently Asked Questions

What is the objective of Spezifische Wärmekapazität von Metallen?
Die spezifische Wärmekapazität mehrerer Metalle mithilfe der Mischungsmethode bestimmen und mit Literaturwerten vergleichen.
How difficult is Spezifische Wärmekapazität von Metallen?
This experiment is rated as Intermediate (High School). It takes approximately 40 minutes to complete.
What safety precautions are needed for Spezifische Wärmekapazität von Metallen?
Key safety precautions include: Hot metals and boiling water — burn risk; Use tongs to transfer hot metals; Do not touch hot metals with bare hands.
What materials are needed for Spezifische Wärmekapazität von Metallen?
The main materials required are: Metal samples (Al, Cu, Fe), Distilled water, Boiling water.
What results should I expect from Spezifische Wärmekapazität von Metallen?
Aluminum should give the largest temperature rise in the water (highest specific heat), followed by iron, then copper. Measured values should be within 10-20% of accepted values.