Electron Affinity
Which element has the most exothermic (most negative) electron affinity?
Select the correct option:
🔒 Solution Hidden from View
Submit your answer to unlock the detailed step-by-step solution.
More classification of elements and periodicity in properties Practice Questions
Which element has the highest electron affinity?
Which element has the highest electron affinity?
Why does lead show a more stable +2 oxidation state than +4 while carbon at the top of the same grou...
Why does lead show a more stable +2 oxidation state than +4 while carbon at the top of the same grou...
The placement of hydrogen in the periodic table is debated; which property allows it to be placed al...
The placement of hydrogen in the periodic table is debated; which property allows it to be placed al...
If two elements differ greatly in electronegativity, what type of chemical bond is most likely to fo...
If two elements differ greatly in electronegativity, what type of chemical bond is most likely to fo...
Why does the effective nuclear charge experienced by valence electrons increase across a period desp...
Why does the effective nuclear charge experienced by valence electrons increase across a period desp...
Why is the first ionization enthalpy of oxygen slightly lower than that of nitrogen, contrary to the...
Why is the first ionization enthalpy of oxygen slightly lower than that of nitrogen, contrary to the...
Why does atomic radius increase down a group even though the nuclear charge also increases with each...
Why does atomic radius increase down a group even though the nuclear charge also increases with each...
Why do the first elements of each group, such as lithium, beryllium, and boron, often show anomalous...
Why do the first elements of each group, such as lithium, beryllium, and boron, often show anomalous...
An element has the outer electronic configuration ending in 3d^5 4s^1; to which block of the periodi...
An element has the outer electronic configuration ending in 3d^5 4s^1; to which block of the periodi...
An element belongs to period 3 and group 16 of the periodic table; what is its total number of valen...
An element belongs to period 3 and group 16 of the periodic table; what is its total number of valen...
How does the valency of main-group elements with respect to oxygen typically vary as one moves acros...
How does the valency of main-group elements with respect to oxygen typically vary as one moves acros...
As one moves from sodium to chlorine across the third period, how does the acidic or basic nature of...
As one moves from sodium to chlorine across the third period, how does the acidic or basic nature of...
Browse all classification of elements and periodicity in properties questions →
About This Question
- Subject
- chemistry
- Chapter
- classification of elements and periodicity in properties
- Topic
- electron affinity
- Difficulty
- Medium
- Year
- 2025
Solution
Correct Answer:
Cl
- Definition: Electron affinity is the energy change when an electron is added to a neutral gaseous atom.
- Expected Trend: Should increase (become more negative) moving up a group (Cl<F).
- The Discrepancy (F vs Cl):
- Fluorine is very small. When an electron is added to its 2p valence shell, it experiences intense electron-electron repulsion from the highly concentrated existing electrons.
- Chlorine has its valence shell (3p) at a greater distance. It is larger, so it can accommodate the extra electron with significantly less repulsion.
- Outcome: Energy released is higher for Chlorine. Its electron affinity is the most negative in the periodic table (−349 kJ/mol).
This medium difficulty chemistry question is from the chapter classification of elements and periodicity in properties, covering the topic of electron affinity. It appeared in the 2025 exam.
Looking for more practice? Explore all chemistry questions or browse classification of elements and periodicity in properties questions on RankGuru.