Start free

Chemistry · Periodicity of Elements and Periodic Properties

NEET (UG) 2025 — Question 44

Which of the following statements are true?

A. Unlike Ga that has a very high melting point, Cs has a very low melting point.

B. On Pauling scale, the electronegativity values of N and Cl are not the same.

C. Ar,K+,Cl−,Ca2+\mathrm{Ar}, \mathrm{K}^{+}, \mathrm{Cl}^{-}, \mathrm{Ca}^{2+}, and S2−\mathrm{S}^{2-} are all isoelectronic species.

D. The correct order of the first ionization enthalpies of Na,Mg,Al\mathrm{Na}, \mathrm{Mg}, \mathrm{Al}, and Si is Si>Al>Mg>Na\mathrm{Si}>\mathrm{Al}>\mathrm{Mg}>\mathrm{Na}.

E. The atomic radius of Cs is greater than that of Li and Rb.

Choose the correct answer from the options given below

  1. Option A:

    A, B and E only

  2. Option B:

    C and E only

    Correct
  3. Option C:

    C and D only

  4. Option D:

    A, C and E only

Answer: B

Step-by-step solution

(C) Ca2+,K+,Ar,Cl−,S2−\mathrm{Ca}^{2+}, \mathrm{K}^{+}, \mathrm{Ar}, \mathrm{Cl}^{-}, \mathrm{S}^{2-} all species have 18 electrons that's why these are isoelectronic species.

(E) Radius order Cs>Rb>K>Na>Li\mathrm{Cs}>\mathrm{Rb}>\mathrm{K}>\mathrm{Na}>\mathrm{Li}

Answer key and solution verified before publishing.

Practise Periodicity of Elements and Periodic Properties

Start with this question, then two more from the same chapter — with a tutor that explains every step. Free.

Solve a similar one free
Exam
NEET (UG) 2025
Paper
2025 paper
Subject
Chemistry
Chapter
Periodicity of Elements and Periodic Properties
Topic
Periodicity in Chemical Properties (Ionization Energy, Electron Affinity, Electronegativity)

More Periodicity of Elements and Periodic Properties questions from this paper

Which of the following statements are true? A. Unlike Ga that has a… | NEET (UG) 2025 PYQ with Solution · DhiX AI