Periodic Table
Systematic study of any thing is Science. Chemistry is a material science, systematically studying the matter of the universe. The matter is available in the form of elements or compounds. The detailed study of elements by various Chemists led to the finding that there is some order and recurrence in the properties of these elements and there were many efforts to classify them. The Russian Chemist, Dmitri Mendeleyev succeeded in providing a very useful classification of the elements, known as Mendeleyev Table. Since there is some periodicity in the arrangement of the table, this is called as Periodic Table of Elements. According to the Mendeleyev s periodic Law, the physical and chemical properties of the elements are the periodic function of their atomic weights. In other words, when elements are arranged in the increasing order of atomic weights, similar elements recur after intervals (Chugh, K.L. 4.1).
This arrangement of Elements in a Tabular form is very useful and handy in the hands of Scientists, Chemists and Engineers.
The salient features of Periodic Table
The elements are arranged in the ascending order of their Atomic weight, to be more precise, Atomic number. Depending on the recurring nature of Chemical and Physical properties, the elements are placed in an ascending order of periods, 1 to 7. The number of elements accommodated in the periods1 to 6 are 2,8,8,18,18, and 32 .
Irrespective of their atomic weight, Elements having similar Chemical properties are grouped into respective groups. In the modern long periodic table, the groups are classified into four blocks, namely, s, p, d, and f depending the electronic configuration of the elements.
The s block elements, of group I and II, are highly reactive Alkali and alkaline earth group of metals. The p block elements, of group IIIA to VIIA are mostly non metals, with some metals. Group VIIA elements are all non metal with electro negative character, that is with high electron affinity. Group VIIIA elements are inert as their outermost shell is fully saturated and consequently have the highest ionization energy and un reactive. The d block elements, IIIB to VII B,VIII, IB, and IIB are all metals with low reactivity, consequently some of them are called noble metals. The f block elements are also metals with low reactivity.
The atoms are thus arranged and located in a table form giving important informations like Name, Symbol, atomic Number, Atomic Weight, Oxidation state, and Physical properties like melting point , Boiling point density.
Uses of periodic Table.
Periodic Table is a very useful document for Academicians - students and professors of Chemistry, Research Chemists, Industrial professionals R D Chemists, Chemical Engineers and Chemical consultants.
Academicians use this to teach the chemical nature with respect to electronic configuration of elements. One can predict how an element will behave seeing the location of the element in Periodic Table. For example, The element Potassium, being located in the first group, it is Electro positive, will react with any electro negative element, say Chlorine. Similarly Silicon being in the middle of the Periodic Table is not a very reactive element.
Chemists, Chemical Engineers and R D Professionals find is as a very useful and handy tool, a one page document, having many useful data available at hand. It is very use full for developing Industrial Chemical process.
Wherever Chemicals are encountered, say Custom houses, Forensic Laboratories, Chemical Analytical Labs etc, Periodic Table will be referred.
Example.1 Process development. Suppose an assignment of developing a process for the manufacture of 30 Hydrochloric acid is given. The process involves Hydrogen, Chlorine and
Oxygen. From the Oxidation state given in the Periodic Table, 1 and -1 for Hydrogen and Chlorine respectively the Equation is HCl HCl, writing the molecular equation, it is H2 Cl2 2HCL. Now, to develop the process, the first step is to develop the Mass Balance. The required atomic molecular masses for Hydrogen, Chlorine, and Water ( water, H2O constitute 70 in the commercial acid,) can be takenCalculated from the Periodic Table. The physical state at which these elements, H and Cl are available, can be assessed from the meltur, Selenium, flouorine bromine and Iodine), The higher period elements are Metals, the metallic property progressively increasinf as we go down in the periodic table.
The rise in ionization energy as we pass from the s elements of the group. I to the p elements of group VIII is due to the increasing effect of the nucleus. (Akhmetov, N.30). The first group element have only one electron in the outr most shell and so have the least ionization energy and so they are higly reactive and can easily form positive Ion. As we progress from s group elements to P elements Ionisation energy increases and consequently reactivity decreases. But the pgroup elements exibit electron affinity, and they can accept electron forming negative Ions. This phenomenon is highest in Group VII elements, Halogens. Thus halogens are most reactive among the P group elements
The tendency to form complexes is most pronounced in elements in the long period of the Mendeleyev periodic system and especially group VIII elements (Alexeyev 228). ing point and boiling point data available in the Periodic Table (Perry). Here in this case Hydrogen is available as a gas as seen from the boiling point.
Systematic study of any thing is Science. Chemistry is a material science, systematically studying the matter of the universe. The matter is available in the form of elements or compounds. The detailed study of elements by various Chemists led to the finding that there is some order and recurrence in the properties of these elements and there were many efforts to classify them. The Russian Chemist, Dmitri Mendeleyev succeeded in providing a very useful classification of the elements, known as Mendeleyev Table. Since there is some periodicity in the arrangement of the table, this is called as Periodic Table of Elements. According to the Mendeleyev s periodic Law, the physical and chemical properties of the elements are the periodic function of their atomic weights. In other words, when elements are arranged in the increasing order of atomic weights, similar elements recur after intervals (Chugh, K.L. 4.1).
This arrangement of Elements in a Tabular form is very useful and handy in the hands of Scientists, Chemists and Engineers.
The salient features of Periodic Table
The elements are arranged in the ascending order of their Atomic weight, to be more precise, Atomic number. Depending on the recurring nature of Chemical and Physical properties, the elements are placed in an ascending order of periods, 1 to 7. The number of elements accommodated in the periods1 to 6 are 2,8,8,18,18, and 32 .
Irrespective of their atomic weight, Elements having similar Chemical properties are grouped into respective groups. In the modern long periodic table, the groups are classified into four blocks, namely, s, p, d, and f depending the electronic configuration of the elements.
The s block elements, of group I and II, are highly reactive Alkali and alkaline earth group of metals. The p block elements, of group IIIA to VIIA are mostly non metals, with some metals. Group VIIA elements are all non metal with electro negative character, that is with high electron affinity. Group VIIIA elements are inert as their outermost shell is fully saturated and consequently have the highest ionization energy and un reactive. The d block elements, IIIB to VII B,VIII, IB, and IIB are all metals with low reactivity, consequently some of them are called noble metals. The f block elements are also metals with low reactivity.
The atoms are thus arranged and located in a table form giving important informations like Name, Symbol, atomic Number, Atomic Weight, Oxidation state, and Physical properties like melting point , Boiling point density.
Uses of periodic Table.
Periodic Table is a very useful document for Academicians - students and professors of Chemistry, Research Chemists, Industrial professionals R D Chemists, Chemical Engineers and Chemical consultants.
Academicians use this to teach the chemical nature with respect to electronic configuration of elements. One can predict how an element will behave seeing the location of the element in Periodic Table. For example, The element Potassium, being located in the first group, it is Electro positive, will react with any electro negative element, say Chlorine. Similarly Silicon being in the middle of the Periodic Table is not a very reactive element.
Chemists, Chemical Engineers and R D Professionals find is as a very useful and handy tool, a one page document, having many useful data available at hand. It is very use full for developing Industrial Chemical process.
Wherever Chemicals are encountered, say Custom houses, Forensic Laboratories, Chemical Analytical Labs etc, Periodic Table will be referred.
Example.1 Process development. Suppose an assignment of developing a process for the manufacture of 30 Hydrochloric acid is given. The process involves Hydrogen, Chlorine and
Oxygen. From the Oxidation state given in the Periodic Table, 1 and -1 for Hydrogen and Chlorine respectively the Equation is HCl HCl, writing the molecular equation, it is H2 Cl2 2HCL. Now, to develop the process, the first step is to develop the Mass Balance. The required atomic molecular masses for Hydrogen, Chlorine, and Water ( water, H2O constitute 70 in the commercial acid,) can be takenCalculated from the Periodic Table. The physical state at which these elements, H and Cl are available, can be assessed from the meltur, Selenium, flouorine bromine and Iodine), The higher period elements are Metals, the metallic property progressively increasinf as we go down in the periodic table.
The rise in ionization energy as we pass from the s elements of the group. I to the p elements of group VIII is due to the increasing effect of the nucleus. (Akhmetov, N.30). The first group element have only one electron in the outr most shell and so have the least ionization energy and so they are higly reactive and can easily form positive Ion. As we progress from s group elements to P elements Ionisation energy increases and consequently reactivity decreases. But the pgroup elements exibit electron affinity, and they can accept electron forming negative Ions. This phenomenon is highest in Group VII elements, Halogens. Thus halogens are most reactive among the P group elements
The tendency to form complexes is most pronounced in elements in the long period of the Mendeleyev periodic system and especially group VIII elements (Alexeyev 228). ing point and boiling point data available in the Periodic Table (Perry). Here in this case Hydrogen is available as a gas as seen from the boiling point.
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