Удельная теплоёмкость металлов

Сравнение теплоёмкости алюминия, меди и железа

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

Цель

Определить удельную теплоёмкость нескольких металлов методом смешения и сравнить с табличными значениями.

Предпосылки

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.

Предупреждения по безопасности

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

Требуемые СИЗ

goggles lab_coat

Материалы

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

Оборудование

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

Процедура

1

Weigh each metal sample accurately. Record masses.

3 мин
2

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

12 мин Handle hot water carefully
3

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

2 мин
4

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

5 мин Hot metal — use tongs
5

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

5 мин
6

Repeat steps 3-5 for copper and iron.

15 мин
7

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

5 мин

Ожидаемые результаты

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.

Уборка

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

Frequently Asked Questions

What is the objective of Удельная теплоёмкость металлов?
Определить удельную теплоёмкость нескольких металлов методом смешения и сравнить с табличными значениями.
How difficult is Удельная теплоёмкость металлов?
This experiment is rated as Intermediate (High School). It takes approximately 40 minutes to complete.
What safety precautions are needed for Удельная теплоёмкость металлов?
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 Удельная теплоёмкость металлов?
The main materials required are: Metal samples (Al, Cu, Fe), Distilled water, Boiling water.
What results should I expect from Удельная теплоёмкость металлов?
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.