Имитация бомбовой калориметрии

Измерение энергетической ценности продуктов методом калориметрии

Thermochemistry Intermediate (High School) 45 мин ~$10,00

Цель

Измерить энергетическую ценность (калорийность) различных продуктов питания, сжигая их и измеряя тепло, переданное воде.

Предпосылки

A simple food calorimeter uses the heat from burning food to raise the temperature of water. By measuring the mass of food burned and the temperature rise of the water, the energy content can be calculated. This demonstrates why some foods have more calories than others.

Предупреждения по безопасности

  • Open flame — keep flammables away
  • Burning food produces smoke — ventilate
  • The can will get hot — do not touch with bare hands

Требуемые СИЗ

goggles lab_coat

Материалы

  • Food samples (10 g each)
    Peanuts, cashews, marshmallows, chips
  • Distilled water (400 mL)
  • Aluminum foil (1 sheet)
    For makeshift shield

Оборудование

Empty aluminum soda can Ring stand and ring Needle or pin (mounted) Lighter Thermometer Analytical balance (0.01 g)

Процедура

1

Measure 100 mL of water and pour into the soda can. Record the initial temperature.

3 мин
2

Set up the can on the ring stand. Position a mounted needle below the can to hold the food sample.

5 мин
3

Weigh a food sample (e.g., one peanut) accurately. Impale it on the needle.

2 мин
4

Light the food sample with the lighter. Position it under the can to heat the water.

5 мин Open flame — be careful
5

When the food stops burning, immediately stir and record the maximum water temperature.

2 мин Can is hot
6

Calculate energy: q = m(water) × c × ΔT. Convert to kJ/g or Cal/g.

5 мин
7

Repeat for different food types. Compare measured values with nutritional labels.

15 мин
8

Discuss why measured values are lower than label values (heat lost to surroundings).

5 мин

Ожидаемые результаты

Nuts (high fat) should give the highest energy per gram (~25 kJ/g measured vs ~25 kJ/g label). Marshmallows (sugar) ~15 kJ/g. Measured values will be 30-50% lower than label values due to heat losses.

Уборка

Allow everything to cool. Dispose of food residue. Rinse the can and clean the work area.

Детали

Категория
Thermochemistry
Сложность
Intermediate (High School)
Продолжительность
45 мин
Прим. стоимость
$10,00
Шаги
8
Материалы
3

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Frequently Asked Questions

What is the objective of Имитация бомбовой калориметрии?
Измерить энергетическую ценность (калорийность) различных продуктов питания, сжигая их и измеряя тепло, переданное воде.
How difficult is Имитация бомбовой калориметрии?
This experiment is rated as Intermediate (High School). It takes approximately 45 minutes to complete.
What safety precautions are needed for Имитация бомбовой калориметрии?
Key safety precautions include: Open flame — keep flammables away; Burning food produces smoke — ventilate; The can will get hot — do not touch with bare hands.
What materials are needed for Имитация бомбовой калориметрии?
The main materials required are: Food samples, Distilled water, Aluminum foil.
What results should I expect from Имитация бомбовой калориметрии?
Nuts (high fat) should give the highest energy per gram (~25 kJ/g measured vs ~25 kJ/g label). Marshmallows (sugar) ~15 kJ/g. Measured values will be 30-50% lower than label values due to heat losses.