Periodic Classification of Elements

are classified on the basis of similarities in their properties.

Döbereiner grouped the elements into triads and gave the Law of Octaves.

Mendeléev arranged the elements in increasing order of their and according to their chemical properties.

Mendeléev even predicted the existence of some yet to be discovered elements on the basis of gaps in his .

Anomalies in arrangement of elements based on increasing atomic mass could be removed when the elements were arranged in order of increasing ,a fundamental property of the element discovered by .

Elements in the Modern Periodic Table are arranged in columns called groups and 7 horizontal rows called .

Elements thus arranged show periodicity of properties including , valency or combining capacity and metallic and non-metallic character.

The eighth element after lithium is .

The law of octaves was the first logical attempt to classify elements on the basis of .

are atoms of the same element having different atomic mass but same atomic number.

Fourteen elements that follow lanthanum called .

Fourteen elements following actinium called .

The law states that "the physical and chemical properties of the elements are periodic function of their atomic numbers".

The vertical column in the periodic table is called as .

Noble gases are also known as .

is the combining capacity of an element.

is defined as the volume occupied by one mole atoms of the element at its melting point, in solid state.

– The distance between the centre of the nucleus and the outermost shell of an isolated atom.

The minimum energy needed to remove the outermost electron from the neutral atom in the gaseous state is energy.

is the amount of energy released when an electron is added to an isolated gaseous atom.

is the tendency of an atom to attract electrons towards itself in a molecule of a compound.

The tendency of an element to lose electrons and form positive ions (cations) is called

Periodic Classification of Elements

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