Periodic Table — Definition, Formula, Properties & Uses | AllChemicals | AllChemicals

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.

Key Facts

Term Periodic Table

Index All "P" terms

Synonyms Periodic table of elements, Mendeleev's periodic table, element chart

Frequently Asked Questions

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.

What is Periodic Table used for?

Is Periodic Table hazardous?

More "P" Terms

P-type Semiconductor Pairing Pairing Energy Palladium Pd Parachor [P] = M(γ)^(1/4) / (ρ_L - ρ_V) Paramagnetic χ_m > 0; unpaired electrons; μ = √(n(n+2)) BM (n = unpaired electrons) Paramagnetism Partial Ionic Character % ionic = (1 - e^(-Δχ²/4)) × 100% Partial Pressure Partial Pressure p_i = x_i × P_total; P_total = Σp_i Particulate Matter Parts Per Million ppm = mg/L (water) or mg/kg; = (mass solute/mass solution) × 10⁶

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