The Road to Entropy – The kinetic theory of gases & heat capacity

I believe that an improved approach to teaching thermodynamics can be created by starting with the atomic theory of matter and then explaining the connections between this theory and macroscopic thermodynamic phenomena. This micro-to-macro approach arguably began in the late 19th century when a small group of scientists, namely Rudolf Clausius, James Clerk Maxwell, andContinue reading “The Road to Entropy – The kinetic theory of gases & heat capacity”

The Road to Entropy – Clausius, Gibbs, and increasing entropy

At the conclusion of his famed 1865 paper announcing the discovery of a new property of matter that he named entropy, Rudolf Clausius stated: the entropy of the universe tends to a maximum. This statement came as a total surprise to me as there was no prior supportive discussion behind it, and it had meContinue reading “The Road to Entropy – Clausius, Gibbs, and increasing entropy”

The Road to Entropy – Clausius undaunted

Have you ever experienced that wondrous “Eureka!” moment of insight when you’ve discovered some hidden secret of nature? Archimedes did when he realized that the volume of water displaced is equal to the volume of the body submerged. Kekulé did when discovered benzene’s structure. Hubble did when he discovered that the stars are all movingContinue reading “The Road to Entropy – Clausius undaunted”

The Road to Entropy – James Joule and the power of his curiosity (video)

James Joule could have observed what he did and then done nothing with it. Instead, he became driven to understand and explain it and so discovered the mechanical equivalent of heat, a forerunner of the concept of energy and the 1st law of Thermodynamics. His story is a good one, an inspiring one, an exampleContinue reading “The Road to Entropy – James Joule and the power of his curiosity (video)”

The Road to Entropy – Sadi Carnot’s use of analogy to create his “flawed” masterpiece (video)

The commercialization of the high-pressure steam engines by the Cornish Engineers of Britain inspired Sadi Carnot, a French military engineer, to analyze these engines and seek the theories to guide their improvement. If you’re interested in doing a deep dive into Sadi Carnot’s work, here are two excellent references. I go into much more depthContinue reading “The Road to Entropy – Sadi Carnot’s use of analogy to create his “flawed” masterpiece (video)”

The oldest surviving steam engine is on display at the Henry Ford Museum of Innovation in Michigan

I was traveling in Michigan this past week and took a day to visit the Henry Ford Museum of Innovation. All I can say is, WOW! Together with the adjacent Greenfield Village, well worth the visit. The Innovation Museum offers great displays of engine technologies, including the oldest surviving steam engine in the world, aContinue reading “The oldest surviving steam engine is on display at the Henry Ford Museum of Innovation in Michigan”

The Road to Entropy – Phil Hosken on Richard Trevithick and the invention of the high-pressure steam engine (video)

As shared in my previous post (here), the historical road to entropy started with Denis Papin’s development of the piston-in-cylinder assembly and Thomas Newcomen’s and James Watt’s subsequent efforts to commercialize and continuously improve fire engines or atmospheric engines built around this assembly. Steam at atmospheric pressure was employed in these engines, not as aContinue reading “The Road to Entropy – Phil Hosken on Richard Trevithick and the invention of the high-pressure steam engine (video)”

The Road to Entropy – The Newcomen and Watt “Steam” Engines (videos)

The road to entropy began with the 18th century development of the “steam” engine by Thomas Newcomen and James Watt. But steam was not the driving force in these engines. So what was? And what was the purpose of the steam? Check out this video for the answers: Note the shout-out in the video toContinue reading “The Road to Entropy – The Newcomen and Watt “Steam” Engines (videos)”

Riddle me this: why does dS = 0 for reversible, adiabatic expansion?

While attending an event in Syracuse, New York, I got to talking with an older chemical engineer who had once worked with my dad at Bristol-Myers Laboratories. I shared that I was writing a book on thermodynamics and we spoke some about this. At the conclusion, he looked at me and said, “You know, IContinue reading “Riddle me this: why does dS = 0 for reversible, adiabatic expansion?”

Riddle me this: what is the physical significance of T∆S in Gibbs’ maximum work equation?

Remember this? Maximum work = -∆Grxn = -(∆Hrxn – T∆Srxn) At some point toward the end of undergraduate thermodynamics, we were taught this equation.  Unfortunately, most of us, myself included, graduated without actually understanding it.  Why?  You already know the answer, just by looking at it.  Because entropy is involved.  While many have a reasonableContinue reading “Riddle me this: what is the physical significance of T∆S in Gibbs’ maximum work equation?”