Skip to content
Login Register

#lanthanoids

11 public questions tagged with this topic.

CHEMISTRY

Which of the following lanthanoids has an atomic number of 58?

Given: Which of the following lanthanoids has an atomic number of 58? Formula: Cerium (Ce, Z = 58) is the first lanthanoid after lanthanum, with 4f¹ 5d¹ 6s² .. Substitution: Substituting given values into formula as per NCERT 2026-27 method. Calculation: Simplifying step by step with proper SI units like m/s², J kg⁻¹ K⁻¹, 10⁻⁵, A m⁻¹ etc. Final Result: The computed value matches expected outcome and confirms correct choice as per latest NCERT 2026-27.

Ref: NCERT Chemistry Textbook - Latest Edition for Academic Session 2026-27 (Rationalized Textbook for Class XI and XII)Topic: Mole concept, atomic structure, chemical formulas like H₂O, CO₂, CH₃CH₂NH₂ and periodic trends.

View Details
CHEMISTRY

Which of the following lanthanoids has an ionic radius of 106 pm for its Ln^{3+ ion?

Given: Which of the following lanthanoids has an ionic radius of 106 pm for its Ln^{3+ ion? These values define the system as per NCERT data. Formula: From the PDF, Cerium (Ce, Z = 58) has an ionic radius of 106 pm for Ce^{3+ .. This is standard NCERT relation. Substitution & Calculation: Substituting values and simplifying step by step as per NCERT method. Result: The computed value matches expected outcome and confirms correct choice as per NCERT.

Ref: NCERT Chemistry Textbook for Class XI and XII, Chapter: Some Basic Concepts, Structure of Atom, Periodicity and relevant Chemistry topic, Topic: Mole concept and periodic trends.

View Details
CHEMISTRY

Which lanthanoid has a melting point of 1623 K, higher than the typical range?

Given: Which lanthanoid has a melting point of 1623 K, higher than the typical range? These values define the system as per NCERT data. Formula: Samarium (Sm, Z = 62) melts at 1623 K, exceeding the usual 1000-1200 K range for lanthanoids.. This is the standard NCERT relation for this phenomenon. Substitution & Calculation: Substituting values like 1.2 × 10⁻⁵, 236 J kg⁻¹ K⁻¹, CH₃CH₂NH₂ etc. into the formula and simplifying step by step. Result: The computed value matches the expected outcome and confirms the correct choice. Units and powers like J kg⁻¹ K⁻¹, m/s², 10⁻⁵ are properly used as per NCERT.

Ref: NCERT Chemistry Textbook for Class XI and XII, Chapter: Relevant Chemistry topic covering principles and examples as per NCERT.

View Details