position of an element in the periodic table

The position of an element in the periodic table is generally determined by its electronic configuration e.g. electronic configuration of sodium is 2, 8, 1 i.e., it has three shells and one electron in the outermost shell. Hence, it is placed in period..

The number of elements in these periods is based on the way electrons are filled into various shell..

Periodic Table and Valency of Elements - a) Group IA, IIA and IIIA consists of metals of normal elements. They have 1, 2, or 3 valence electrons which they can easily donate to acquire the configuration of nearest noble gas. They become positively c..

Group IA, IIA and IIIA consists of metals of normal elements. They have 1, 2, or 3 valence electrons which they can easily donate to acquire the configuration of nearest noble gas. They become positively charged i.e., cations. ..

Hydrogen is the first element of the periodic table. Its atomic number is 1, which indicates the presence of only one electron in the atom of hydrogen. This electron is present in its first shell. Hydrogen resembles both alkali metals (group I A) as well as halog..

Position of Chlorine in the Periodic Table - 1.Chlorine is placed second after fluorine in group VIIA. 2. Other members of this group are fluorine, bromine, iodine and astatine (the last member is radioactive). 3. Members of this group are called 'halogens' meaning sal..

Position of Oxygen and Sulphur in the Periodic Table - 1. Oxygen is the first member of the group VIA and sulphur is the second member of the group VI..

Predicting Period, Group and Block of an Element - Knowing the electronic configuration, one can predict the period, which corresponds to the principal quantum number of the valence shell. The block of the element corresponds to the sub shell, which receives ..

Introduction - With the rapid development of Chemistry and the discovery of new elements, it was necessary to develop a simple way to study and remember the numerous properties of the elements and their compounds. This gave rise to the necessity of classification of the ele..

Dobereiner's Triads - In the famous atomic theory of John Dalton (1805), it was suggested that the atoms of an element have a characteristic mass. So, attempts were made to classify elements on the basis of their atomic masses. In the year 1829, Johann Wolfgang Dobereiner, a Ger..