Chemistry involves study of various elements present around us. Some of these elements resemble each other while others are absolutely different. This difference and similarity between elements is due to their chemical and physical properties. On the basis of these properties, elements have been categorised into separate groups or blocks on the periodic table. The periodic table is a tool to study diverse elements found in nature and their classifications.
The portion on the right side of the periodic table represents p-block that contains some unique and important elements called as p-block elements. Here we concern ourselves about how to study p-block elements for IIT JEE exam. This block includes elements classified under columns 13- 18 (column 3A-8A) barring Helium (He) that is excluded from the block. The p-block elements are called so because their valence electrons lie in the p orbital. This orbital can carry a maximum of six electrons and hence the six columns in this block. It means that the first column elements have one valence electron in their p-orbital; the second column has two valence electrons and so on. Depending on their column number, these elements are called group 13, 14,15,16,17 and 18 elements. There are 36 elements in all in the p-block of the periodic table.
p-block is unique in the sense that it holds metal, metalloids as well as non- metals, a property no other block on the periodic table has. The p-block elements are essentially the most important and abundant elements found on earth. The only thing common in this otherwise diverse collection of metallic and non-metallic elements is that all of them have their valence electrons orbiting in the p orbital.
p-block Metallic elements
- P block metals are lustrous and conductors of heat and electricity.
- Their tendency to lose electrons easily makes them highly unstable.
- They easily react with non- metals to form ionic compounds.
- They have high meting point.
Special p block metals- Gallium ( Ga) in the 13th column can melt at room temperature. Tin (Sn) from 14th column, a vital constituent of alloys like solder and bronze, is found in abundance in earth’s crust. A toxic metal Lead (Pb) from the same column was earlier used in making toys, utensils, and paints but since its toxic effects came to be known the use of lead is constrained.
p-block Non- metallic elements
- The maximum elements in p block are non metals which do not lose electrons easily.
- They have low boiling points.
- They are non- lustrous and brittle elements.
- They are bad conductors of heat and electricity.
- Some of them occur as solids others as gases except Bromine (Br) that is liquid at room temperature.
Special p block non- metals- Graphite is the physical form of Carbon (C) besides diamond where this element is found in solid form. Otherwise, Carbon reacts readily with other elements to form compounds. We all know how essential carbon-di-oxide is for biotic life on earth. Phosphorus (Ph) and Iodine (I) are essential mineral found on earth that are very important for healthy functioning of a human body.
These elements have characteristic properties of metals as well as non-metals.
Silicon (Si) is perhaps the most famous metalloid and is one of the richly available substances. It is used in making glass and chips for electronic instruments. Its shiny appearance and fragile tendency makes it a metalloid.
The above information gives you an ample explanation of p-block elements and their characteristics. This knowledge can help you understand p-block elements in better light for your boards and JEE/AIPMT preparation.