Enthalpy Change ∆H Of A Reaction - Reaction Enthalpy
Chapter Name : Thermodynamics |
Sub Topic Code : 102_11_06_04_02 |
Topic Name : Enthalpy Change ∆H Of A Reaction - Reaction Enthalpy |
|
Sub Topic Name : Standard Enthalpy Of Reactions |
|
Introduction
·
The
standard enthalpy of reaction is the enthalpy change for a reaction when all
the participating substances are in their standard states. It is denoted as ?H? .
·
The standard condition for most substances is
298 K and 1 bar.
The benefit of a measuring standard ?H is that we can relate one value of ?H? to another, since they occur under the same conditions.
Pre-Requisites:
· Thermodynamic terms
· The state of a system
· Enthalpy
Activity:
The change in
energy taking place when an athlete has an energy drink. Is similar to reaction
enthalpy.
Real Life Question:
What is the
significance of standard enthalpy of reaction?
Key Words / FlashCards
| Key Words | Definitions (pref. in our own words) |
|---|---|
| Enthalpy | It is same as energy at low and moderate pressure |
| Reaction enthalpy | The enthalpy change accompanying a chemical reaction |
| Standard reaction enthalpy | It is the enthalpy change for a reaction when all the participating substances are in their standard states. It is denoted as ?H? . |
Learning aids / Gadgets
| Gadgets | How it can be used |
|---|---|
| An athelete before and after taking an energy drink | The change in energy taking place when an athlete has an energy drink. Is similar to reaction enthalpy. Energy change after a rigorous day at work. |
Real life uses :
Standard reaction enthalpy helps in easy calculation
as it provides uniform conditions for all substances.
Places to visit :
kitchen
Practical examples around us
| Examples | Explainations |
|---|---|
| Energy drink | The change in energy taking place when an athlete has an energy drink. Is similar to reaction enthalpy. |
What you learn in Theory:
The need for
calculating standard enthalpy.
What you learn in Practice:
Changes take place
when reactants change into products