A mixture can be separated into its components using physical means. An element is a substance consisting of a single type of atom. The periodic table organizes the chemical elements into an arrangement of rows and columns. Molecules consist of two or more atoms whose particles are chemically bonded. Early humans could not explain the vast amount of substances, or how they transformed. Therefore, they could only explain chemical phenomena through the intervention of the gods. Greek philosophers believed that all matter consisted of four elements – fire, air, water, and earth. Not until modern times did chemists manage to identify the building blocks of matter. Through this, they could bring order to the various materials in the world and explain chemical transitions between substances.
FROM MATTER TO ELEMENTS
Compounds, mixtures, and elements differ in how they are divided into components. An element consists of atoms of the same kind and cannot be broken down by physical or chemical methods. As Anton Chekhov said in the 19th century: “For the chemist, there is nothing impure on this earth.” There may have been a deeper meaning in this Russian writer’s standpoint, but according to scientists, Chekhov was wrong. For the chemist, there is a significant difference between mixtures and compounds.
DISTINGUISHING MIXTURES
Wine is an example of a mixture. If the wine is heated, it begins to boil at around 78 degrees. After a certain time, the boiling point rises to 100 degrees. If pure alcohol such as ethanol is heated, the temperature remains steady at 78 degrees.
Ethanol is a pure compound, while wine contains several substances, mostly ethanol and water. If the vapors formed when the wine is heated are passed through a tube to another container, they condense into liquid form. The liquid thus obtained drips into the second container, and ethanol is thereby separated from the wine. This separation occurs due to the different boiling points of water and ethanol. In addition to this distillation process, there are other ways to separate the components of liquid mixtures. Through filtration, we can obtain different particle sizes, and with liquid chromatography, we can determine the different solubilities of substances. The best answer to the question of what the difference is between mixtures and compounds is that mixtures can be separated by physical means, but not compounds.
DIFFERENT TYPES OF MIXTURES
Mixtures like wine often have a uniform appearance outwardly. Similarly, seawater, which consists of salt dissolved in water. Alloys like brass or bronze are mixtures of metals with specific material properties. Bronze is copper with up to one-third tin in it, and brass is copper with an addition of zinc. In emulsions like salad dressings made of oil and vinegar, on the other hand, we can clearly see drops of one type of liquid inside another type of liquid.
COMPOUNDS AND ELEMENTS
Although elements, unlike mixtures, cannot be separated into their components by mechanical means, most can be further broken down by other means. For example, water is split into oxygen and hydrogen when an electric current is applied. Like iron, gold, or sulfur, oxygen and hydrogen cannot be further divided by chemical means. All these substances are elements.
