Discussion Overview
The discussion revolves around the discrepancy between two sources regarding the expression for kinetic energy in gases, specifically whether the average kinetic energy for a mole of gas is represented as K.E.avg = 3/2 RT or if the total kinetic energy for a mole is equal to 3/2 RT. The scope includes conceptual clarification and technical reasoning related to thermodynamics and kinetic theory.
Discussion Character
- Conceptual clarification
- Debate/contested
- Technical explanation
Main Points Raised
- One participant notes that Exam Krackers states the average kinetic energy for a mole of gas is K.E.avg = 3/2 RT, while their chemistry book claims the total kinetic energy for a mole of gas is also 3/2 RT, leading to confusion about the definitions.
- Another participant questions the units of the expression 3/2 RT, seeking clarity on its dimensional analysis.
- A participant provides the value of R and calculates the units for 3/2 RT as J/mol, suggesting that the average kinetic energy for one molecule can be expressed in terms of mean square speed, leading to a conclusion that supports their chemistry book's claim.
- Another participant confirms that (3/2)RT represents the total energy per mole of a monatomic ideal gas and introduces the average kinetic energy of a molecule as (3/2)kBT, noting the relationship between the Boltzmann constant and R.
- There is uncertainty expressed regarding why the Exam Krackers book states that the average kinetic energy for a mole of gas is 3/2 RT, indicating a potential conflict in the sources.
Areas of Agreement / Disagreement
Participants do not reach a consensus on which source is correct regarding the definitions of average and total kinetic energy for a mole of gas. Multiple competing views remain, particularly concerning the interpretation of the expressions and their implications.
Contextual Notes
The discussion highlights potential limitations in the definitions used in different sources, as well as the dependence on the context of the terms "average" and "total" kinetic energy. There is also an unresolved aspect regarding the interpretation of the units and their implications for the claims made by each source.