Theories in Physics: Entropy Part One

Have you ever wondered why ice cream on a hot summer day melts, or why balloons lose their air if they aren’t tied properly? The reason behind these happenings is Entropy, a concept that is essential to our understanding of both physics and chemistry.

Entropy is most commonly classified as the direct measurement of disorder; however, this definition is misleading to an extent. A more reliable and robust method of understanding entropy is through probability. An example used by many scientists is as follows. If you have two solids that exist due to six bonds that exist in both. Bonds in chemistry and physics store energy known as quanta. Energy and heat are two values that share a direct proportion, so as energy increases so does heat.

Between the two solids, the same amount of quanta can be stored in numerous patterns. The differentiation between the patterns allows for Microstates to appear, which are simply the different patterns the quanta are able to exist as. For example, if there were eight quanta available to be distributed within the two solids there are numerous different combinations for the particular amounts stored within the two solids. Solid one could store eight, seven, six, five, four, three, two, one, and zero quanta while solid two could store zero, one, two, three, four, five, six, seven, and eight quanta respectively. Some of these combinations have a higher chance of occurring compared to others which are due to the greater number of Microstates for the given combination compared to the other combinations.

You may be wondering “Where exactly does Entropy fit into all this?” or “How does probability fit into finding Entropy?”. Well, all of these questions will be answered in part two where we combine our knowledge of microstates with probability.

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