Why Does Chemistry “Matter”?
Matter. It is what makes up the entire universe, and makes us what we are today. From magnificent glowing stars millions of light years away, to the tiny, dim night light in a child’s room, it consists of matter. This concept of understanding the make-up of everything we know and will know is not a straight forward thing either. It can take on many different shapes and forms, such as compounds, elements, mixtures and much more. Matter can even go through numerous and exciting changes, making it an intriguing topic to study upon. As scientists have been discovering for thousands of years, science is an incredible thing, and can be very fascinating once you delve into its secrets.
The most basic building block of matter is of course the element. An element is the smallest thing that a substance can be broken down into without splitting atoms. A great example of a common element is the gas Oxygen (O). Another example of elements would be the breaking apart of the compound Sodium Chloride (NaCl), or table salt, as we casually call it. When salt is broken down into its smallest parts, you will have the elements sodium and chlorine left over. These combinations of two or more elements are called a compound. In a compound, the elements are chemically bonded together through a chemical reaction to form something new. As learned in the POGIL activity, the majority of our items that we use and see on a daily basis are compounds. A few examples of these items are water (H2O), Chalk (CaCo3), carbon dioxide (Co2), acetaminophen (C8H9No2), and much more. You would be surprised to know that these reactions are occurring everywhere all the time, even without us knowing it. Not all of these reactions are big, or drastically change the substances interacted with it, but life would be impossible to sustain without them.
These common changes can come in many ways, shapes, and forms, including physical and chemical changes. A physical change is a change to the substance that does not affect what substance is or its chemical makeup. These changes, such as tearing, cutting, dissolving, freezing, evaporating, condensing, affect the substance without changing it molecular makeup, therefore classifying it as a physical change. Chemical changes, on the other hand, do change the substance and its molecular makeup. Examples of these types of changes can be rotting, rusting, digesting, eroding, burning and reacting with an acid. If a chemical change occurs, you cannot get back the original substances without using some form of a chemical or having a chemical reaction occur. It is easy to know when a chemical reaction is occurring to your substance though. Common side effects from a reaction may be smoking, heat expulsion, smell dispersion, bubbles (creation of a gas), formation of a precipitate, and a change in color. As we saw in the iron and sulfur lab, many of these things will occur at the same time. When our reaction occurred, we observed heat expulsion, smoking, and a change in color, and of course, the nasty smell that this experiment is famous for. During this reaction though, not all of the material was used or fused, leaving a mixture left over in the test tube.
A mixture is a combination of two or more substances either dry (such as sand) or in a liquid (such as sugar water). Compared to a pure substance, mixtures are fairly easy to spot. A pure substance is a material that has the same concentration of molecules throughout its entirety, while also only consisting of one type of molecule. Examples of a pure substance might be salt, sugar, and the other items listed previously, as all elements and compounds are pure substances. If you were to look at a mixture at a molecular level compared to a pure substance, it would look drastically different. The mixture would have many different molecules, particles and substances within it, while the pure substance would only have one. Even with the naked eye, these differences are as obvious. A pure substance is usually uniform, while a mixture contains clumps, bubbles, different colors, grain sizes, and textures. Even more surprising is that it is actually easier to separate one of these crazy mixtures than to separate a plain compound, as a chemical reaction is needed for the compound’s separation. As we learned in the Separation of a Mixture Lab, this makes sense as a mixture can be separated fairly easily. Ways to separate a mixture could be boiling, evaporating, sifting, magnetism, filtering, and much more. When you actually dig down to the bottom of these many different forms of matter, it is actually easy and fun to tell them apart and to separate them in the lab!
Chemistry is one of the biggest and fastest growing branches of science out there right now. From searching for cures for diseases such as cancer, HIV, and even the common cold, to just trying to be the discoverer of a new substance, chemistry has brought, and is still bringing joy and learning to millions of people around the globe. As we have learned through our many experiments over the past weeks, matter is the basic building block of everything. Once you get past the nitty gritty, and nuts and bolts of these basic principles (and even these aren’t too difficult), many will discover that this field is fascinating, and has the potential to benefit and affect us as students, and possibly even our society, in the rest of lives soon to come.