Periodic Table

The cause of actinide contraction is the imperfect shielding by 5f-electrons. As we proceed from one element to the next one in the actinide series,…

General Properties of Actinide Series (5f block elements) In 1923 Neils Bohr postulated the existence of an actinide series analogous to the lanthanide series. The…

The atomic size or ionic radii of tri positive lanthanide ions decrease steadily from La to Lu due to increasing nuclear charge and electrons entering…

The Lanthanide Contraction describes the atomic radius trend that the Lanthanide series exhibit. It is a very important phenomenon in determining the characteristics of the…

General properties of Lanthanides Electronic configuration The electronic configuration of Lanthanides is listed in the table. The fourteen electrons are filled in Ce to Lu…

The Lanthanide series include fifteen elements i.e. lanthanum (57La) to lutetium (71Lu). Lanthanum and Lutetium have no partly filled 4f- subshell but have electrons in…

Elements whose f orbital getting filled up by electrons are called f block elements. The elements in which the extra electron enters ( n- 2…

Purple of cassius is only a form of colloidal gold. It is purple or red in colour and after the name of Cassius who discovered…

Formation and structure of ethylene molecule: In ethylene and in other organic compounds having C = C bond, 2s and two 2p orbitals of carbon…

In some compounds like Beryllium Chloride (BeCl2), Boron Trifluoride (BF3), Aluminium Chloride (AlCl3) some atoms have less than 8 electrons in their valence shell. Group…