Question

Elements in the same group or column of the periodic table have similar chemical properties because their atoms have the same _______

Answer 1

Hint : The physical and chemical properties of elements depend on the number of valence electrons. They depend on valence electrons because these are the electrons which participate in chemical reactions. Elements present in the same group have the same number of valence electrons. So, the elements in the same group have similar chemical properties.

Complete Step By Step Answer:
Elements present in the same group or column of the periodic table tend to have similar chemical properties because their atoms have the same valence electrons. The elements in the same period do not have similar chemical and physical properties because the number of valence electrons are different for different elements in the period. There are eighteen groups in the modern periodic table which are further classified into blocks. Remember that the physical and chemical properties of elements depend on atomic number of elements but not on atomic mass.

Note :
We can observe many trends in the periodic table which helps us to memorize the properties of elements easily. Some of the major trends observed in the periodic table are ionic radius, metallic character, electronegativity, ionization energy, electron affinity, atomic radii, chemical reactivity, etc. These trends exist because of similar atomic structure of some elements within groups or periods. We can obtain a lot of information from the periodic table such as symbol of element, atomic number of element, atomic mass, valence electrons and many other properties.