In our everyday life, we come across several materials with distinct properties, based on which we assign a particular application for that material. For instance, the strength of iron provides a significant advantage over wood to make bridges. In chemistry, we classify these materials by segregating their elemental form into three main categories: metals, non-metals, and metalloids. Out of 118 elements present in the modern periodic table, 92 elements are metals, 6 are metalloids, and the remaining 22 are non-metals. In simple terms, the classification is made based on to what degree a material possesses certain properties such as electrical conductivity, thermal conductivity, electronegativity, ionization potential, etc. The nonmetals are a group of elements located on the right side of the periodic table (except for hydrogen, which is on the top left). These elements typically have low melting and boiling points, don’t conduct heat or electricity very well, and tend to have high ionization energies and electronegativity values. In comparison to metals, there is a wider variation in properties among the nonmetals. Let’s discuss a few non-metals and their properties that make them useful in our daily life.
Hydrogen is the smallest and lightest chemical element in the modern periodic table, having only one proton and one electron. Despite its placement in the periodic table above the alkali metals group, hydrogen is a nonmetal because its characteristics differ substantially from those of metals. For instance, unlike most metals, hydrogen is a gas at room temperature, forms cation (H+) more reluctantly, and it forms polar covalent bonds with most of the other chemical elements. The most crucial significance of hydrogen is as an element in the formation of “water,” one of the most essential chemicals for life to exist. Apart from being a crucial element for human existence, it has also aided civilization in exploring the world beyond the atmosphere. NASA and other space agencies use a combination of liquid hydrogen and other gases like oxygen and fluorine as a propellent fuel for rockets and space vehicles. Industrially, hydrogen is used to prepare several useful chemical compounds such as fertilizers, coolants, etc. It is also used as a shielding gas for industrial welding purposes. Hydrogen is extensively used in the energy sector for the extraction and processing of fossil fuels.
Helium, the second most abundant element in the universe, is a colorless, odorless, tasteless, non-toxic, inert noble gas with the atomic number 2 and symbol He. It is the lightest member of the noble gas group of the periodic table, which is a further sub-category of non-metals. The main source of helium in the universe is nuclear fission that converts two hydrogen atoms to helium; however, on earth, helium is commercially recovered from natural gas deposits. Helium is chemically non-reactive, so it is useful for applications such as lasers, where non-flammability is of extreme concern. Because of its low density helium is often used to fill decorative balloons, weather balloons, and airships. Due to its cryogenic properties, helium is widely used in heavy machinery like MRI machines, CT-SCANS, and NMR spectroscopy to protect machines from overheating. Helium is considered a life-saving ingredient when it comes to deep-sea diving. It helps to flush out nitrogen from our body, which can cause nauseous effects below 60-70 ft of water.
Oxygen, one of the most necessary elements for humans, is a non-metallic element with the atomic number 8 and symbol O. It is the third most abundant element in the universe and makes up nearly 21% of the earth’s atmosphere. Chemically, it is known to readily forms oxides with most elements as well as with other compounds. Its primary function in our lives is to provide over body with the required energy through a process called respiration. When we breathe, we take in oxygen and breathe out carbon dioxide. Oxygen is taken from the lungs through hemoglobin and travels to every cell in the body. The mitochondria present in our cells use oxygen to transform nutrients from the digestive process into energy that can be used directly by the cell (ATP). Oxygen is a necessary element required for combustion, an exothermic chemical reaction. In other words, it is impossible to set conventional organic fuels to fire without oxygen, and hence, oxygen a necessary non-metal required for cooking food. In liquid form, oxygen is used widely as an oxidizing agent for use in missiles and rockets, where it reacts with liquid hydrogen to produce the terrific thrust needed for take-off. Astronaut spacesuits carry a nearly pure form of oxygen.
Carbon, a substance that makes around 12% of our human body, is a chemical element with an atomic number 6 and symbol C, and it has a field of study associated with itself called organic chemistry. It is a tetravalent nonmetallic element that has one of the widest spectra of properties. For instance, there are several pure forms of this element including graphite, diamond, fullerenes, and graphene. While graphite is so soft that it can easily form a streak on paper ( as in pencil), diamond is one of the hardest materials to ever exist, even harder than most metals. Carbon is an essential element in fire extinguishers as it shields the oxygen that is required for combustion. The uses of carbon and its compounds are extremely varied. It can form alloys with iron, of which the most common is carbon steel. Graphite is combined with clays to form the ‘lead’ used in pencils used for writing and drawing. It is also used as a lubricant and a pigment, as a molding material in glass manufacture, in electrodes for dry batteries, electroplating, and electroforming, in brushes for electric motors, and as a neutron moderator in nuclear reactors. The more recent discovery of carbon nanotubes, other fullerenes, and atom-thin sheets of graphene has revolutionized hardware developments in the electronics industry and nanotechnology.
Sulfur is a multivalent non-metal, abundant, tasteless and odorless. In its native form sulfur is a yellow crystalline solid. In nature, it occurs as the pure element or as sulfide and sulfate minerals. The principal use of sulfur, however, is in the preparation of its compounds. The most important sulfur compound is sulfuric acid. Other important compounds include sulfur dioxide, used as a bleaching agent, disinfectant, and refrigerant. Sulfur is used in the vulcanization of black rubber, as a fungicide, and in black gunpowder. Most sulfur is used in the production of sulfuric acid, which is perhaps the most important chemical manufactured industrially. The most important of sulfuric acid’s various applications is the production of phosphoric acid, which is used to generate fertilizer phosphates. Mercaptans, an organosulfur chemical family, are added to natural gas sources because of their distinct odor, which allows gas leaks to be easily identified. Others are used in the production of insecticides and herbicides, as well as silver polish. Many foods include sulfites, which are used to bleach paper, and as preservatives. Sulfate derivatives are found in many surfactants and detergents. Each year, 100 million tonnes of calcium sulfate (gypsum) are mined for use in cement and plaster.
Nitrogen, the most abundant chemical present in our atmosphere, is a non-metallic element represented by the symbol N and atomic number 7 in the modern periodic table. It is a crucial element for life and can be found in soil, water, air, plants, and makes up 78.1% of the entire volume of the atmosphere. The mineral source of nitrogen is niter (potassium nitrate). At standard temperature and pressure conditions, nitrogen occurs as an odorless, tasteless, and colorless gas. It is a poor conductor of heat and electricity and lacks metallic luster in solid form. The most common use of nitrogen gas that we may encounter during our daily regime is the preservation of packed food items such as chips, ready-to-eat snacks, drinks, etc. In its nitrous oxide state, it can be used as an anesthetic to relieve pain and relax patients. Nitrogen is used in the manufacturing of incandescent light bulbs as an inexpensive alternative to argon. In our vehicles, a compound of nitrogen called sodium azide is used for instant inflation of airbags on collision. Moreover, in racing-sports vehicles, nitrogen is also used to inflate tiers as moisture present in the normal air can cause pressure fluctuation at high rpm. Liquid nitrogen is often used as a refrigerant. It is used for storing sperm, eggs, and other cells for medical research and reproductive technology. It is also used to rapidly freeze foods, helping them to maintain moisture, color, flavor, and texture. Nitrogen is also one of the most important nutrients required for plant growth. The atmospheric nitrogen is converted into a usable form of nitrogen compound by nitrogen fixation.
Chlorine is a naturally occurring chemical element with the symbol Cl and atomic number 17. It is the second lightest halogen in the periodic table with excellent disinfectant properties. The physical form of chlorine is a diatomic green gas. The word chlorine comes from the Greek word chloros, which means “green,” referring to the color of the gas. Chlorine gas is two and a half times the weight of air, has a strong suffocating stench, and is extremely dangerous. It is a powerful oxidizing, bleaching, and disinfecting agent in both liquid and solid form. It’s a chemical building block that’s utilized to create a variety of items that benefit public health and safety, sophisticated technology, nutrition, security, and transportation. Chlorine chemistry is used in food, water, pharmaceuticals, computers, and cell phones. Contact lenses, air conditioning refrigerants, and solar panels are just a few of the items made with chlorine chemistry, which also includes bullet-resistant jackets, energy-efficient windows, paint, and prostheses. t’s employed in substitution processes and as an oxidizing agent. At some point throughout the manufacturing process, chlorine or its derivatives are used in 85 percent of medications. Chlorine was once widely utilized to manufacture anesthetics like chloroform and carbon tetrachloride (a dry-cleaning solvent). Both of these compounds, however, are now closely regulated since they can harm the liver.
Iodine is the heaviest nonmetallic element represented by symbol I and atomic number 53 in the modern periodic table. It is one of the most essential nutrients that the human body acquires from the diet. If you do not have enough iodine in your body, you cannot make enough thyroid hormone, which can lead to enlargement of the thyroid gland and cause the infamous goiter disease. Many saltwater and plant-based foods contain iodine, and this mineral is most widely available in iodized salt. As a pure element, iodine is a lustrous purple-black solid under standard temperature and pressure conditions. It sublimes (changes from a solid to a gaseous state while bypassing a liquid form) easily and gives off a purple vapor. Although it is technically non-metal, it exhibits some metallic qualities. Apart from fulfilling the physiological need of thyroxine for humans, Iodine also supports the healthy growth of animals like broiler chickens. Iodine also has a variety of uses in the industrial and technology sectors. For instance, the LCD screens that we encounter on daily basis make use of light polarizing films that are manufactured using iodine. Nylon, a popularly known thermoplastic polymer, is vulnerable to high temperatures on its own. To overcome this inefficiency, a combination of Cuprous Iodide and Potassium Iodide is added to the nylon. Iodine also has some remarkable disinfectant properties that can be employed for the sterilization of drinking water, swimming pools, and even for wastewater management.
Fluorine is a non-metallic element with the symbol F and atomic number 9. It is the most electronegative chemical that usually occurs as a pale-colored diatomic gas. It is one of the few elements that will form compounds with noble gases xenon, krypton, and radon. Metals, glass, ceramics, carbon, and water will burn with a bright flame in fluorine. Fluorine was not commercially produced until the Second World War when the development of the atom bomb and other nuclear energy initiatives compelled large-scale production; however, fluorine salts, often known as fluorides, were often used in welding and glass frosting. Nowadays, fluorine compounds can easily be located in several household items, such as freons in refrigerators, sodium fluoride salt in toothpaste, etc. Trace dietary fluorine levels may also impact bone strength. While fluorine compounds are not found in animals, there are natural organofluorines in plants, which typically act as defenses against herbivores. The mineral source of fluorine, i.e. fluorapatite is also used in the manufacturing of decorative warm and cold lights. The non-stick pan that we use to make an omelet is also made of one of a fluorinated compound polymer called Polytetrafluoroethylene (PTFE) or Teflon.
Phosphorus is a non-metallic chemical element with the symbol P and atomic number 15. It is always present in its maximally oxidized state and never exists as a free element on earth. Phosphorus is essential for life as a component of DNA, RNA, ATP (adenosine triphosphate), and the phospholipids that form all cell membranes. The most important elemental form of phosphorus in terms of applications is white phosphorus. It glows in the dark (when exposed to oxygen) with a very faint tinge of green and blue, and it is highly flammable and pyrophoric (self-igniting) upon contact with air. Owing to this property, white phosphorus is used as an additive in napalm. It can easily be found in fireworks. Red phosphorus is in the material stuck on the side of matchboxes, used to strike safety matches against to light them. By far the largest use of phosphorus compounds is for fertilizers as ammonium phosphate.