Greetings,
The next several posts will focus on energy concepts. A focus on energy in chemistry must also involve matter because changes in chemical & physical properties are intertwined with changes in energy. Notice the emphasis on the word, "change": Every chemical system consists of an internal energy, which cannot be measured directly. In other words, the absolute energy of a chemical system cannot be measured in the laboratory. If a Chemist could measure absolute energy, then the act would imply knowledge (and therefore 'measureability') of certain defining chemical properties (such as pressure and volume) at a "zero-energy point" (i.e., the beginning of the heat scale), but the stated premise, simply, cannot be performed.
One may ask, " If we cannot measure absolute energy of any system, then what system's energy can be measured?" The answer is "none", if you believe in a world full of static systems, but that is not the reality of our natural world around us and even within us! In a way, the whole discussion of measuring absolute energy is a moot point because, in terms of energy, there is nothing necessary (nor even useful) to measure until matter undergoes a change! Indeed, we are surrounded by natural systems in states of dynamic flux from every direction and everywhere we go. All matter consists of atoms and/or molecules in a constant state of motion. The extent of molecular level motions for all materials depends on the level of energies (such as light and heat) acting upon atomic-level particles and the level of potential energy binding forces between the particles contained within a chemical system.
There is, however, one main Chemistry reference for which we "pretend" that there are no interatomic binding forces and we "imagine" a constant temperature of 273.15 K plus a constant pressure of 1 atm. In other words, this Chemistry reference also portrays every chemical system contained therein as static (constant energy) and completely unreactive! "How in the world could such a reference ever be useful?", one may ask. So, it may come as a surprise to learn that the Chemistry reference described above is none other than The Periodic Table of The Elements, itself!
And so, things are often not as they would seem (static but really dynamic) and the primary Chemistry reference for the same "things" treats them as existing in a state (static & constant) of which, clearly, they are not! This apparent paradox exists so that the atoms of every element are presented in a standardized energy state; which is the electron configuration ground-state.
All systems of the natural universe are in a dynamic ever-changing energetic state. And so, because all matter consists of atoms undergoing change (thermal, physical, and chemical), Chemists are interested in measuring the effects of those changes on the energies associated with all natural systems.
That's all for this post. I hope this has been enjoyable and useful!
As always, thank you for reading!
A Publication of http://ExcellenceInLearning.biz
The next several posts will focus on energy concepts. A focus on energy in chemistry must also involve matter because changes in chemical & physical properties are intertwined with changes in energy. Notice the emphasis on the word, "change": Every chemical system consists of an internal energy, which cannot be measured directly. In other words, the absolute energy of a chemical system cannot be measured in the laboratory. If a Chemist could measure absolute energy, then the act would imply knowledge (and therefore 'measureability') of certain defining chemical properties (such as pressure and volume) at a "zero-energy point" (i.e., the beginning of the heat scale), but the stated premise, simply, cannot be performed.
One may ask, " If we cannot measure absolute energy of any system, then what system's energy can be measured?" The answer is "none", if you believe in a world full of static systems, but that is not the reality of our natural world around us and even within us! In a way, the whole discussion of measuring absolute energy is a moot point because, in terms of energy, there is nothing necessary (nor even useful) to measure until matter undergoes a change! Indeed, we are surrounded by natural systems in states of dynamic flux from every direction and everywhere we go. All matter consists of atoms and/or molecules in a constant state of motion. The extent of molecular level motions for all materials depends on the level of energies (such as light and heat) acting upon atomic-level particles and the level of potential energy binding forces between the particles contained within a chemical system.
There is, however, one main Chemistry reference for which we "pretend" that there are no interatomic binding forces and we "imagine" a constant temperature of 273.15 K plus a constant pressure of 1 atm. In other words, this Chemistry reference also portrays every chemical system contained therein as static (constant energy) and completely unreactive! "How in the world could such a reference ever be useful?", one may ask. So, it may come as a surprise to learn that the Chemistry reference described above is none other than The Periodic Table of The Elements, itself!
And so, things are often not as they would seem (static but really dynamic) and the primary Chemistry reference for the same "things" treats them as existing in a state (static & constant) of which, clearly, they are not! This apparent paradox exists so that the atoms of every element are presented in a standardized energy state; which is the electron configuration ground-state.
All systems of the natural universe are in a dynamic ever-changing energetic state. And so, because all matter consists of atoms undergoing change (thermal, physical, and chemical), Chemists are interested in measuring the effects of those changes on the energies associated with all natural systems.
That's all for this post. I hope this has been enjoyable and useful!
As always, thank you for reading!
A Publication of http://ExcellenceInLearning.biz