Exams › JEE Main › Chemistry

Identify the sequence that is incorrect.

1. NH₃ < PH₃ < AsH₃ — acidity
2. Li < Be < B < C — first ionization energy
3. Al₂O₃ < MgO < Na₂O < K₂O — basic character
4. Li⁺ < Na⁺ < K⁺ < Cs⁺ — ionic radius

Correct answer: Li < Be < B < C — first ionization energy

Solution

First ionization energy order is Li < B < Be < C because the filled 2s2 of Be makes its IE higher than B's. So 'Li < Be < B < C' (option 1) is the incorrectly arranged sequence.

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 →