- Atomic radius is the distance from the nucleus to the outermost shell.
- Over time, atomic size decreases due to a stronger nuclear pull.
- Down a group, atomic size increases as new shells are added.
- Atomic size depends on the number of shells and the nuclear charge.
- Cations are smaller, anions are larger, and in isoelectronic ions, size decreases with more protons.
Definitions [2]
Definition: Atomic Size (Atomic Radius)
It is the distance between the centre of the nucleus of an atom and its outermost shell.
Definition: Electronegativity
The tendency of an atom in a molecule to attract the shared pair of electrons towards itself is called its electronegativity.
Key Points
Key Points: Atomic Size
Key Points: Electronegativity
- Electronegativity is the ability of an atom to pull shared electrons; it is highest for fluorine (4.0).
- It increases across a period (left to right) and decreases down a group (top to bottom).
- Non-metals have high electronegativity (gain electrons), while metals have low electronegativity (lose electrons).
Concepts [19]
- Significance of Classification of Elements
- Genesis of Periodic Classification
- Modern Periodic Law and the Present Form of the Periodic Table
- Nomenclature of Elements with Atomic Number Greater than 100
- Periodic Table and Electronic Configuration
- The s-Block Elements
- The p-Block Elements
- The d-Block Elements (Transition Elements)
- The f-Block Elements (Inner-transition Elements)
- Metals, Non-metals and Metalloids
- Atomic Size
- Ionic Radius
- Ionization Enthalpy or Ionization Energy (IE) or Ionization Potential (IP)
- Electron Gain Enthalpy
- Electronegativity
- Periodicity of Valence or Oxidation States
- Anomalous Properties of Second Period Elements
- Periodic Trends and Chemical Reactivity
- Classification of Elements and Periodicity in Properties Numericals
