JEE Main 202621 JanuaryEvening Shift
- Exam
- JEE Main
- Year
- 2026
- Date
- 21 January
- Shift
- Evening Shift
- Subject
- Chemistry
- Chapter
- Classification of Elements and Periodicity in Properties
JEE Main 2026 · 21 January · Evening Shift · Chemistry · Classification of Elements and Periodicity in Properties
Given below are two statements : Statement I : The correct order in...
Given below are two statements :
Statement I : The correct order in terms of atomic/ionic radii is .
Statement II : The correct order in terms of the magnitude of electron gain enthalpy is .
In the light of the above statements, choose the correct answer from the options given below :
Statement I : The correct order in terms of atomic/ionic radii is .
Statement II : The correct order in terms of the magnitude of electron gain enthalpy is .
In the light of the above statements, choose the correct answer from the options given below :
Options
- ABoth Statement I and Statement II are false
- BBoth Statement I and Statement II are true
- CStatement I is false but Statement II is true
- DStatement I is true but Statement II is false
Correct answer
C. Statement I is false but Statement II is true
Step-by-step solution
Analyzing Statement I: The order given is Al > Mg > Mg²⁺ > Al³⁺. However, the correct atomic radii order should be Mg > Al because Mg is in group 2 (period 3) while Al is in group 13 (period 3), and moving right across a period decreases radius. The correct order would be Mg > Al > Mg²⁺ > Al³⁺. Therefore, Statement I is FALSE.
Analyzing Statement II: Electron gain enthalpy magnitudes follow: Cl (highest, ~349 kJ/mol) > Br (~325) > S (~200) > O (~141). This is because Cl has the highest tendency to gain an electron due to its position and electronic configuration. Statement II is TRUE.
Since Statement I is false and Statement II is true, the answer is option (3).
Analyzing Statement II: Electron gain enthalpy magnitudes follow: Cl (highest, ~349 kJ/mol) > Br (~325) > S (~200) > O (~141). This is because Cl has the highest tendency to gain an electron due to its position and electronic configuration. Statement II is TRUE.
Since Statement I is false and Statement II is true, the answer is option (3).