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Also Known As
Periodic table of elements, Mendeleev's periodic table, element chart
What is Periodic Table?
The tabular arrangement of the chemical elements ordered by atomic number, electron configuration, and recurring chemical properties. Elements in the same column (group) have similar properties. The periodic table has seven periods (rows) and 18 groups (columns), totaling 118 elements.
Properties & Characteristics
The periodic table is a tabular arrangement of the chemical elements ordered by increasing atomic number (Z) and grouped by similar electronic configurations and chemical properties. It was developed by Dmitri Mendeleev (1869) who predicted the existence of then-unknown elements. Elements in the same vertical column (group) have similar outer electron configurations and chemical behaviour. The table reveals periodic trends: atomic radius, ionisation energy, electronegativity, and metallic character.
Uses & Applications
The periodic table is the most important organisational tool in chemistry: it allows prediction of element properties, compound formulae, reaction types, and physical properties based on position. It is used in: elemental analysis interpretation, catalyst selection, materials design, biochemistry (trace element roles), and in educational settings as the foundation of chemical knowledge.
Safety Information
The periodic table reveals which elements are: highly reactive and hazardous (Group 1 metals, Group 17 halogens), radioactive (all actinides, some lanthanides), toxic heavy metals (Groups 10-15 in periods 5-6), or relatively inert (Group 18 noble gases). Period and group position is a useful first-pass hazard guide.
Always consult the SDS/MSDS before handling any chemical. This information is for educational purposes only.
SynonymsPeriodic table of elements, Mendeleev's periodic table, element chart
Frequently Asked Questions
The tabular arrangement of the chemical elements ordered by atomic number, electron configuration, and recurring chemical properties. Elements in the same column (group) have similar properties. The periodic table has seven periods (rows) and 18 groups (columns), totaling 118 elements.
The periodic table is the most important organisational tool in chemistry: it allows prediction of element properties, compound formulae, reaction types, and physical properties based on position. It is used in: elemental analysis interpretation, catalyst selection, materials design, biochemistry (t…
The periodic table reveals which elements are: highly reactive and hazardous (Group 1 metals, Group 17 halogens), radioactive (all actinides, some lanthanides), toxic heavy metals (Groups 10-15 in periods 5-6), or relatively inert (Group 18 noble gases). Period and group position is a useful first-p…
Editorial standards: Chemical data is sourced from peer-reviewed literature,
CAS Registry, NIST WebBook, and PubChem. Safety information reflects guidance from OSHA, ECHA,
and IAEA. For educational purposes only — always consult official SDS documentation and qualified
professionals before handling chemicals.
