Calorimetry

Amount and rate of heat transfer using iron spheres and liquid nitrogen

Dean Campbell | Tue, 06/04/2024 - 11:00

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When iron spheres at room temperature are added to liquid nitrogen, the nitrogen boils as heat is transferred in from the iron. The amount of liquid nitrogen boiled depends on the amount of heat transferred, which depends on the mass of the iron added. However, the rate at which liquid nitrogen boils depends on the surface area of the iron in contact with the liquid nitrogen. These phenomena can be studied with experiments which measure the mass lost by the boiling liquid nitrogen.

Using My Marbles: Connecting Surface Area and Calorimetry with Temperature Curves and Thermochromic Cups

Dean Campbell | Sat, 07/30/2022 - 15:02

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The importance of surface area can be illustrated by adding spherical solids at known sizes and temperature to other substances at different temperatures and then monitoring the rates of temperature changes of the system over time. Larger spheres (with less surface area per sample) exchanged heat with water more slowly than smaller spheres, and less thermally conductive glass spheres exchanged heat with water more slowly than iron spheres. Additional, more colorful demonstrations are described in which small glass spheres cool thermochromic plastic cups more quickly than larger glass spheres.

Developing a Model for Enthalpy of Solution—Reframing the Approach

Ben Meacham | Wed, 03/17/2021 - 10:30

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Ben Meacham decided to alter his approach to teaching about enthalpy and focus on getting students to first develop the mathematical model for enthalpy of solution so they could eventually apply it to make predictions for different solutes being dissolved. In this blog post he shares the process he used with his class.

To Inquiry or not to Inquiry . . .

Sarah Kong | Wed, 06/04/2014 - 18:20

Here is something to ponder as you think about your lab experiences this year: I have been using an excellent inquiry lab for the past few years. I think it does a fabulous job guiding the students through the amazing (yet often dull to students) world of specific heat equations and learning about calorimetry. However, this semester, I returned to the old, traditional calorimetry lab. I wan