Elements in the same group have similar properties because they have the same number of valence electrons in their outermost shell. Elements in the same period have different properties because the number of valence electrons in their outermost shells differ.

Rows and Periods Elements are listed in order of increasing atomic number from left to right. Each row of the periodic table is called a period and each column of the periodic table is called a group (or family). Elements within the same period or group have similar properties.

1 Answer. The elements in the same group has similar number of valence electrons. They have identical number of electrons in their outermost shell. e.g. All the alkali metals in Group 1 have 1 valence electron, so they all tend to react the same way with other substances.

The s-block and p-block elements are so called because their valence electrons are in an s orbital or p orbital respectively. They are also called Typical Elements to distinguish them from the transition and inner transition series.

General Characteristics of s-block Elements They are soft metals, possess low melting and boiling points, have the largest atomic radii in their corresponding periods and are good conductors of heat and electricity. They have low values of ionisation energies and are hence highly electropositive.

The p-block is the region of the periodic table that includes columns IIIA to column VIIIA and does not include helium. There are 35 p-block elements, all of which are in p orbital with valence electrons. The p-block elements are a group of very diverse elements with a wide range of properties.

S- block consists of group 1 known as alkali metals and group 2 known as alkaline earth metals. P-block consists of group 13, 14, 15, 16, 17 and 18. D block consists of group 3, 4, 5, 6, 7, 8, 9, 10, 11 and 12.

If the element is in the p block, then the number of the group can be determined by the formula: (number of valence electrons + 10). 3. If the element is in the d block, then the number of the group can be determined by the formula: [number of electrons in (n-1) d subshell] + (number of electrons in (n) s subshell).

F block elements are divided into two series, namely lanthanoids and actinoids. These block of elements are often referred to as inner transition metals because they provide a transition in the 6th and 7th row of the periodic table which separates the s block and the d block elements.

Properties of transition elements include:

1. have large charge/radius ratio;
2. are hard and have high densities;
3. have high melting and boiling points;
4. form compounds which are often paramagnetic;
5. show variable oxidation states;
6. form coloured ions and compounds;
7. form compounds with profound catalytic activity;

first transition series i.e., 3d series is from Scandium to Zinc. Atomic numbers are from 21 to 30.

A transition metal is one that forms one or more stable ions which have incompletely filled d orbitals. On the basis of this definition, scandium and zinc do not count as transition metals – even though they are members of the d block. The zinc ion has full d levels and does not meet the definition either.