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Technical data

Specific heat capacity of different liquids with Cobra SMARTsense

Article no: P7404669

Principle

Different temperature increases show that substances respond differently to supplied energy and therefore have different specific heat capacities. In this experiment, students investigate the specific heat capacity of different liquids by heating water and glycerin with the same energy input and measuring the temperature change as well as the supplied energy. Using the Cobra SMARTsense Energy sensor, power and energy are recorded digitally, while a temperature sensor measures the temperature rise. In this way, students recognize the relationship between supplied energy and temperature change, as well as the substance-specific ability to store heat.

Tasks

Students set up a simple student calorimeter with a temperature probe and heating coil.
They successively heat defined quantities of water and glycerin at the same heating power over a specified period and record temperature and power.
They determine the temperature change from the measurement data and calculate the supplied thermal energy.
They then calculate the specific heat capacity of the investigated liquids and compare the results. Possible influences, such as the heat capacity of the calorimeter or measurement uncertainties, are discussed.

Learning objectives

Through this experiment, students understand the concept of energy and the relationship between thermal energy, mass, and temperature change. They recognize specific heat capacity as a substance-dependent quantity and as a measure of a material’s ability to store heat, and they learn about the structure and function of a calorimeter. By using digital sensors and software for data acquisition and evaluation, they develop skills in analyzing experimental data.

Benefits

Easy implementation and promotion of technical understanding with a self-assembled calorimeter made from standard laboratory equipment.
Promotes understanding of energy transformations during heating processes.
Strong everyday relevance (e.g., explanation of energy transfer when boiling water).
Quantitative evaluation through measurement of temperature, power, and energy using digital sensors (Cobra SMARTsense).
Combination of classical experiment and modern data acquisition.
Opportunity to discuss measurement deviations compared to literature values.
Fast and simple experiment preparation (experiment instructions available).