Question

Define D block elements in Modern Periodic Table.

Answer 1

• The modern periodic table is an arrangement of all the elements known by their increasing atomic number and recurring chemical properties.
• It is a tabular display of 118 chemical elements which consists of horizontal rows called periods and vertical columns are called groups.

D block elements:

• D block elements are the elements that lie from the third group to the twelfth group of the modern periodic table.
• The number of elements present in the d-block of the periodic table is 40. Four series of transition elements (each series having 10 elements) constitute a d-block.
• The valence electrons of these elements fall under the d orbital.
• In the D block elements have electrons (1 to 10) present in the d-orbital of the penultimate energy level and the outermost s-orbital (1-2).
• D block elements are referred to as transition elements as their position between s and p block elements and they exhibit transitional behavior between s and p block elements.
• Example: scandium (Sc), titanium (Ti), vanadium (V), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni).