The material can be divided into several categories. Two main categories are mixtures and pure substances. A pure substance has a constant composition. All specimens of a pure substance have exactly the same composition and properties. Each sucrose sample (table sugar) is composed of 42.1% carbon, 6.5% hydrogen and 51.4% oxygen by mass. Each sucrose sample also has the same physical properties such as melting point, color and softness, regardless of the source from which it is isolated. Imagine how different your life would be without mobile phones (Figure 1.17) and other smart devices. Mobile phones are made from many chemical substances that are extracted, refined, purified and assembled using a complete and deep understanding of chemical principles. About 30% of the elements found in nature are found in a typical smartphone. The case/body/frame consists of a combination of robust and durable polymers composed mainly of carbon, hydrogen, oxygen and nitrogen [acrylonitrile butadiene styrene (ABS) and polycarbonate thermoplastics] and light and strong structural metals such as aluminum, magnesium and iron. The screen consists of specially tempered glass (quartz glass reinforced by the addition of aluminum, sodium and potassium) and is covered with a conductive material (e.g. indium tin oxide).
The PCB uses a semiconductor material (usually silicon); commonly used metals such as copper, tin, silver and gold; and lesser-known elements such as yttrium, praseodymium and gadolinium. The battery is based on lithium ions and a variety of other materials, including iron, cobalt, copper, polyethylene oxide and polyacrylonitrile. Boiling is the process by which a substance passes from the liquid phase to the gas phase. You can get water to do this at room temperature by placing it in a heavy container and removing all the air – setting it to zero air pressure – and then the water comes out of the liquid phase and passes into the gas phase! Substances such as hydrogen, methane and carbon dioxide, which are found on Earth as gas, are found on outer planets like Saturn as ice. Substances such as iron, silicon, carbon, which are found on Earth in solid form, are found in the sun in the form of ionized gases or plasmas! Matter is defined as everything that occupies space and has mass, and it is all around us. Solids and liquids are an obvious matter: we can see that they take up space, and their weight tells us that they have mass. Gases are also matter; If gases did not take up space, a balloon would not inflate (increase its volume) when filled with gas. All the materials we see in our daily lives (from ice to chairs to water) are made of matter. Matter can be divided into different states such as solid, liquid and gaseous depending on intermolecular forces and particle arrangement. These three forms of matter can be transformed from one matter state to another by modifying certain environmental factors (for example, increasing or decreasing pressure and temperature). For example, ice can be converted from solid water to liquid water by increasing the temperature. The law of conservation of matter summarizes many scientific observations about matter: it states that there is no detectable change in the total amount of matter present when matter is transformed from one type to another (a chemical change) or changes between solid, liquid or gaseous states (a physical change).
Beer brewing and battery operation are examples of material preservation (Figure 1.8). During beer brewing, the ingredients (water, yeast, grains, malt, hops and sugar) are converted into beer (water, alcohol, carbonic acid and flavorings) without any real loss of substance. This is especially evident during the bottling process, when glucose is converted to ethanol and carbon dioxide and the total mass of substances does not change. This is also evident in a lead-acid car battery: raw materials (lead, lead oxide and sulfuric acid) that can produce electricity are converted into other substances (lead sulfate and water) that do not produce electricity without changing the actual amount of the substance. The material can be classified according to its physical and chemical properties. Matter is something that occupies space and has mass. The three states of matter are solid, liquid and gaseous. Physical transition involves the transformation of a material from one matter state to another without changing its chemical composition. Although there are just over 100 elements, tens of millions of chemical compounds result from various combinations of these elements. Each compound has a specific composition and has certain chemical and physical properties that distinguish it from all other compounds. And of course, there are countless ways to combine elements and compounds in different mixtures.
A summary of the distinction between the different main classifications of the subject is presented in (Figure 1.11). Three types of materials are solids, liquids and gases. It is important to understand the particulate nature of matter. The particles that make up matter are not “small solid pieces” or “small liquid droplets”, but atoms and molecules. The physical properties of these atoms and molecules determine their state. There are three states of matter and here is the description of the different states of matter: The properties of the combined elements differ from those of the free or non-combined state. For example, white crystalline sugar (sucrose) is a compound formed from the chemical combination of the element carbon, which is a black solid in one of its uncombined forms, and the two elements hydrogen and oxygen, which are colorless gases when not combined. Free sodium, an element that is a soft, shiny metallic solid, and free chlorine, an element that is a yellow-green gas, combine to form sodium chloride (table salt), a compound that is a white crystalline solid.