Exams › JEE Main › Chemistry

For Na+, Mg2+, F− and O2−, the correct order of increasing ionic radii is:

1. O2− < F− < Na+ < Mg2+
2. Na+ < Mg2+ < F− < O2−
3. Mg2+ < Na+ < F− < O2−
4. Mg2+ < O2− < Na+ < F−

Correct answer: Mg2+ < Na+ < F− < O2−

Solution

O2-, F-, Na+, Mg2+ are all isoelectronic (10 electrons). Radius decreases as nuclear charge rises, so increasing order is Mg2+(12p) < Na+(11p) < F-(9p) < O2-(8p).

Related JEE Main Chemistry questions

• For the element having atomic number 120, which symbol and IUPAC systematic name are correctly paired?
• Which sequence correctly represents the ionization energies of carbon, nitrogen, and oxygen atoms?
• Identify the sequence that is not arranged correctly.
• Identify the statement that is not correct:
• As stated by the Periodic Law, the changes in elemental properties depend on their
• Choose the sequence that arranges the following species in increasing order of size:

⚔️ Practice JEE Main Chemistry free + battle 1v1 →