Analysis of The P-block Elements of The Periodic Table

Introduction

The p-block of the Periodic table consists of groups 13, 14, 15, 16,17 and 18. The elements in the p-block have their outermost electrons in the p-orbital of their shells, hence they are called p-block elements. The p-block consists of solids and gases, and metalloids and non-metals. The p-block elements do not follow any specific trend for their occurrence. Some are usually found in combination with other elements, for example oxygen and sulphur: while some are found free, for instance, the noble gases. Some elements are abundant in nature while others are rare. Aluminum, silicon, oxygen are abundant while heavier elements are rare.

General trends for p-block elements: atomic size decreases along the period and increases down the group, the first ionization enthalpy of the p-block elements generally decreases down the group and increases on moving from left to right along a period, nonetheless, there are certain exceptions, e.g., the first ionization enthalpy of a group 16 element is lower than that of a group 15 element. Electron affinity generally becomes more negative on moving from left to right along a period, because it becomes easier for the atom to gain electrons due to increased nuclear attraction, and becomes less negative down the group as it becomes harder for an atom to gain electrons. Electronegativity increases along the period and decreases down the group. Fluorine, oxygen, and nitrogen are the most electronegative elements in the periodic table in the given order.

Along the period the metallic character decreases, whereas non-metallic character increases, and on moving down the group the metallic character increases, whereas non-metallic character, decreases. Among p-elements there are elements that can be both cations and anions (A1, Ca, Ti, Se, Pb, PB, Sb, Bi) or only anions (В, С, Sі, N, Р, Аs, О, Те, Р, СІ, Вг, І, Аt). 

Applications Of P-block Elements in Daily Life:

Group III Elements:

Group three elements are the elements which contain three electrons in the outer most shell. These element include B, Al, Ga, In, Th. These compounds are quite useful in daily life and can be used for many different purposes, such as construction, electronics and production of other materials. Applications of some important elements are discussed below.

1. Boron: The atomic number of boron is 5 and its mass number is 10.811. The melting point of boron is very high, 2,200 °C (4,000 °F). Boron is a useful material and can be used in rocket fuel igniter and in pyrotechnic flare. The most important compounds of boron are boric (or boracic) acid, borax (sodium borate) and boric oxide. These can be found in eye drops, mild antiseptics, washing powders and tile glazes. Borax used to be used to make bleach and as a food preservative. Boric oxide is also used in making tough Pyrex glass, and Fiberglass textiles and insulation are made from borosilicate glass. Sodium octoborate is a flame retardant and B-10 is used in nuclear reactors as it is a good absorber of neutrons.
2. Aluminum: Aluminum is an important element which found in abundance on earth. It has an atomic number of 13, atomic weight of 26.9815, and melting point of 660 °C (1,220 °F). It is used in diverse fields of life such as architecture, electronics and transportation. As aluminum is strong, it is suitable for architectural work, it conducts electricity so it is suitable to be used for wiring, and as it is light-weight, the vehicles made from it are easier to maneuver and more fuel-efficient.
3. Gallium: The Atomic number of gallium is 31 and its relative atomic mass is 69.723. the Melting point of Gallium is 29.7646°C. Gallium arsenide has a similar structure to silicon and therefore it is a useful silicon substitute for the electronics industry. It is an important component of many semiconductors and is used in red LEDs (light emitting diodes) because of its ability to convert electricity to light. Solar panels on the Mars Exploration Rover also contained gallium arsenide. It is also used in semi-conductors, LEDs and for recording temperatures that would vaporize a thermometer.

Group IV Elements:

Group IV elements of the periodic table contain four electrons in their outermost shell. These are perhaps a few of the most common and the most important elements of the periodic table. These elements include carbon, silicon, germanium, tin and lead. Some of these elements hold an extremely important place in the human civilization and have always done so.

1. Carbon: The atomic number of carbon is 6 and its atomic weight is 12. Carbon has a Melting point of 3550 oC. Three common crystalline allotropes are graphite, diamond, and (usually) fullerenes. Carbon (in the form of coal is used as a fuel. Graphite is used for pencil tips, high temperature crucibles, dry cells, electrodes and as a lubricant. Diamonds are used in jewelry and in industry for cutting, drilling, grinding, and polishing. Carbon black is used as the black pigment in printing ink. The 14C radioactive isotope is used in archaeological dating.
2. Silicon: the Atomic number of silicon is 14 and its relative atomic mass is 28.085. Silicon is used to make alloys including aluminium-silicon and ferro-silicon. These are used to make dynamo and transformer plates, cylinder heads engine blocks and machine tools and to deoxidise steel. Silicone oil is a lubricant and is added to some cosmetics and hair conditioners. Silicone rubber is used as a waterproof sealant in bathrooms and around windows, pipes and roofs. It is also used as a semiconductor in solid-state devices. Silicon carbides are important as abrasives and are also used in laser.
3. Tin: Atomic number of tin is 50 and its atomic weight is 118.69. The melting point is 231.97 °C and it is used for many purposes such as tin-plating, plate-glass production, alloys such as pewter, bell metal, bronze, making ceramic bodies opaque, as an abrasive, for making fabrics heavier, and in dentifrices. Organic tin compounds act as stabilizers in certain plastics and as wood preservatives. Elemental tin is non-toxic but organic tin compounds used as fungicides etc. are toxic.

Group V Elements:

Group V elements are those elements which contain 5 electrons in their outermost shell. These elements are non-metal in nature and include elements such as nitrogen, phosphorus, arsenic, antimony and bismuth. Some daily life uses of some of these elements shall be discussed below.

1. Nitrogen: Atomic number of nitrogen is 7 and its relative atomic mass is 14.007. And Melting point is −210.0°C. Nitrogen is a very important constituent of macronutrients such as proteins and is therefore essential to proper functioning of both humans and plants. Nitrogen is important to the chemical industry. It is used to make fertilisers, nitric acid, dyes, nylon, and explosives. Ammonia, which is one of the most important compounds of nitrogen, is produced by the Haber process and around 150 million tons of ammonia are produced in this way every year. It is used to preserve foods, in the electronics industry and in annealing stainless steel and other steel mill products. Annealing is a heat treatment that makes steel easier to work. Liquid nitrogen can also function as a refrigerant.
2. Phosphorus: the atomic number of phosphorus is 15 and its atomic weight is 30.97. its melting point is 44.2oC. Phosphorus is an important plant nutrient and is majorly used in the production of fertilizers. Phosphorus is used in the manufacture of safety matches (red phosphorus), pyrotechnics and incendiary shells. Phosphorus is also used in steel manufacture and in the production of phosphor bronze. It’s also used in LEDs.

Group VI Elements:

Group VI elements are the elements which have six electrons in the outermost shell. Along with sulphur, selenium, tellurium, and polonium, the element which is the fundamental to the existence of life, that is, oxygen, is present in group VI. These elements normally exist in -2 oxidation state and are non-metals, with oxygen being the only gaseous element.

1. Oxygen: The atomic number of oxygen is 8 and its atomic weight is 16. It exists as a gas at room temperature with the molecular formula of O2. The most important application of oxygen is that this gas is utilized for respiration in the vast majority life-forms, including humans, plants, aquatic species, fungi and microorganisms. It is carried in the blood as oxyhemoglobin and leads to the formation of ATP. Also, oxygen is reactive and therefore reacts with a number of compounds to form oxides such as sulphur dioxide, magnesium oxide, and alminium oxide. It also aids combustion, and can its compounds such as KMnO4 can be used as an oxidising agent in organic reactions.
2. Sulphur: sulphur is also an important-block element from the sixth group. Its atomic number is 16, and its atomic weight is 32. It exists as a solid at room temperature. It is very important for two reasons, first sulphur is a vital microelement. Sulfur is included in many biomolecules for example, proteins, amino acids (cysteine, cystine, methionine, etc.), hormones (insulin), vitamins (B), and a lot of Sulfur is contained in hair, bones, nervous tissue. Second, sulphur is used in the production of one of the most economically valuable substance, the sulphuric acid by Contact process. Sulphuric acid is used in a large number of industries such as paint and textile.

Group VII Elements:

Element of the seventh group of the periodic table are also known as halogens, and their ions are known as halides. The halogens contain seven electrons in their outermost shell and only need to gain one electron to attain stable configuration. The group contains elements in all three physical states, i.e., fluorine and chlorine are gases at room temperature, bromine is a liquid and iodine and astatine are solids.

1. Fluorine: Fluorine is the most electronegative element of the periodic table. Its atomic number is and its atomic weight is 19. The melting of fluorine is -220ºC. Its common uses include the compound Teflon which used as a non-stick coating Fluoride is also added to toothpaste and drinking water to help reduce tooth decay and is present in the clay used in some ceramics. It is also involved with generating nuclear power and, is used in producing fluoroquinolones, which are antibiotics.
2. Chlorine: The second halogen is chlorine; its atomic number is 17 and its atomic weight is 35.5. Chlorine has many industrial uses for e.g., it is used to disinfect drinking water and swimming pools and its compound Sodium hypochlorite (NaClO) is the main component of bleach. It is present in CFCs and PVC polymer which is used to make pipes, etc. and chlorine is also used in pharmaceutics. It is used in treating infections, allergies, and diabetes as well as for sterilizing hospital equipment. It also used to be a component of insecticides.
3. Bromine and Iodine: the third and fourth halogens are bromine and iodine. The atomic number of bromine is 35 and its mass number is 79.9. The atomic number of iodine is 53 and its mass number is 126.9. Bromine is used in flame retardants and pesticide methyl bromide; and is takes part in the production of gasoline and photographic film. It is also found in fire extinguishers and in drugs treating pneumonia and Alzheimer’s disease.

Iodine is essential for proper thyroid functioning and is therefore added to table salt. It is also important as a disinfecting agent, and is used to treat open wounds. Silver bromide is important in photography. 

Group VIII Elements:

Group VIII elements of the periodic table are known as noble gases. They have a complete outermost shell and are highly stable and unreactive. Noble gases normally exist as individual atoms and are relatively very rare. They are gaseous in nature and include helium, neon, argon, krypton, xenon and radon.

1. Helium: Helium is the smallest noble as and its atomic number is 2. The atomic mass of helium is 4 and it boils at 4.2 K (−268.95 °C; −452.11 °F). Tt is the second of the two elements in the first period. It is used for superconducting magnets, such as those needed in nuclear magnetic resonance imaging and nuclear magnetic resonance. Helium is used as a component of breathing gases to replace nitrogen and that is because of its low solubility in fluids, particularly in lipids, as nitrogen can be absorbed into the cells under pressure. Helium can also be used in weather balloons.
2. Neon and Argon: the atomic number of neon is10 and its atomic mass is 20.1. The atomic number of argon is 18 and its atomic mass in 39.9. as these gases are inert, they can be used to create inert mediums for different substances. Liquid neon can be used for cryogenics because it has over 40 times more refrigerating capacity than liquid helium and over three times more than liquid hydrogen.

Argon is considered the best option for use as a dry-suit inflation gas for scuba diving. It can also be used in the formation of air-sensitive compounds which may react with nitrogen. “Solid argon is also used for the study of very unstable compounds, such as reactive intermediates, by trapping them in an inert matrix at very low temperatures”. It can also be used as a filtering gas for incandescent light bulbs.

Conclusion:

The elements of the p-block elements are very important to human civilization. They are diverse in nature, including metals and non-metals. These compounds can be used in fields as varied as architecture, polymer production and pharmaceutics. The p-block elements comprise of groups III-VIII (or 13-18) and normally form anions by gaining electrons. Some elements are more abundant, for example, carbon, silicon and oxygen, whereas the noble gases are rare in nature. The lack of reactivity of noble gases allows them to be used as inert reaction medium. In short, the elements of p-block have numerous applications and can be put to multiple uses in daily life.