Measurement Of ∆U And ∆H
Chapter Name : Thermodynamics |
Sub Topic Code : 102_11_06_03_01 |
Topic Name : Measurement Of ∆U And ∆H |
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Sub Topic Name : Measurement Of ∆U And ∆H |
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Introduction
• Every chemical and physical process has some energy associated with it. • This energy is measured using a calorimeter which works on the technique of calorimetery. • Calorimetry measurements can be made in 2 ways : - At constant volume - At constant pressure
Pre-Requisites:
• Thermodynamic terms • The state of a system • Enthalpy • Heat capacity
Activity:
Cereal box- It has an energy value written on it which is found by measuring the combustion heat value of food.
Real Life Question:
How can we measure the energy associated with any chemical process?
Key Words / FlashCards
| Key Words | Definitions (pref. in our own words) |
|---|---|
| Calorimetry | It is the act of measuring the energy associated with chemical reactions or physical changes. |
| Calorimeter | It is an object used for measuring energy change associated with a chemical or physical process. |
| Heat capacity | The number of heat units needed to raise the temperature of a body by one degree. |
Learning aids / Gadgets
| Gadgets | How it can be used |
|---|---|
| Calorimeter | It is an object used for measuring energy change associated with a chemical or physical process. |
Real life uses :
- Food companies use Calorimetry to calculate the energy content of their product. - At chemical plants, new reaction/process is first tried at small-scale in a calorimeter to see how much heat is evolved, to know if the cooling system will be able to handle it or not.
Places to visit :
Home.
Practical examples around us
| Examples | Explainations |
|---|---|
| Cereal box | The energy associated with combustion of food is measured using calorimeter. |
What you learn in Theory:
Measurement of energy associated with a physical or chemical process.
What you learn in Practice:
Different types of calorimeters.