First, second and third ionisation enthalpies of the 3d series (NCERT Table 4.2)3d श्रेणी की प्रथम, द्वितीय और तृतीय आयनन एन्थैल्पी (NCERT सारणी 4.2)First, second and third ionisation enthalpies of the 3d series (NCERT Table 4.2)

Class 12 Chemistry · Chapter 4 · interactive diagram

Parts and what they mean

• First ionisation enthalpy (प्रथम आयनन एन्थैल्पी) — Rises only slowly (631 → 906 kJ/mol): the 4s electron is removed and the extra d electrons shield it.
• Second ionisation enthalpy (द्वितीय आयनन एन्थैल्पी) — Generally rises; a big jump for Cr (1592) and Cu (1958).
• Third ionisation enthalpy (तृतीय आयनन एन्थैल्पी) — Highest; peaks for Mn and Zn, dips for Fe.
• High IE₂ of Cr and Cu (Cr और Cu की उच्च IE₂) — Cr⁺ is d⁵ and Cu⁺ is d¹⁰ — removing the second electron breaks a stable half-filled or filled set.
• High IE₃ of Mn (and Zn) (Mn (और Zn) की उच्च IE₃) — Mn²⁺ is d⁵ and Zn²⁺ is d¹⁰ — very stable, so the third electron is hard to remove.
• Low IE₃ of Fe (Fe की कम IE₃) — Fe²⁺ (d⁶) → Fe³⁺ (d⁵): losing one electron gives the stable d⁵ set.
• Axes (अक्ष) — x: Sc to Zn; y: kJ/mol. All values from NCERT Table 4.2.

Original diagram drawn by Simple Learning Hub, based on the NCERT textbook. Report a mistake