Which of the following statements is correct?

Question

Question

This question was previously asked in

SSC MTS 2024 Official Paper (Held On: 30 Oct, 2024 Shift 3)

Chlorine has the highest electron affinity, while fluorine has the highest electronegativity.
Fluorine has the highest electron affinity, while chlorine has the highest electronegativity.
Fluorine has the highest electron affinity and the highest electronegativity.
Fluorine has the highest electron affinity, while bromine has the highest electronegativity

Answer 1

The correct answer is Chlorine has the highest electron affinity, while fluorine has the highest electronegativity..

Key Points

Chlorine has the highest electron affinity due to its optimal atomic size, which allows it to efficiently gain an electron and release energy in the process.
Fluorine has the highest electronegativity (value of 3.98 on the Pauling scale), as it has a strong tendency to attract shared electrons in a chemical bond due to its small size and high nuclear charge.
Electron affinity refers to the energy released when a neutral atom in the gas phase gains an electron to form a negative ion.
Electronegativity, on the other hand, measures the ability of an atom to attract shared electrons in a chemical bond.
The difference arises because fluorine's small size causes strong electron-electron repulsions, slightly reducing its electron affinity compared to chlorine.

Additional Information

Electron Affinity:
- The trend of electron affinity generally increases across a period and decreases down a group in the periodic table.
- Chlorine's electron affinity is approximately 349 kJ/mol, the highest among all elements.
- Fluorine's electron affinity is slightly lower at about 328 kJ/mol due to increased electron repulsion in its compact atomic structure.
Electronegativity:
- Electronegativity increases across a period and decreases down a group, following the periodic trend.
- Fluorine, being the most electronegative element, plays a key role in various chemical reactions, including the formation of polar covalent bonds.
Electron-Electron Repulsion:
- Smaller atoms like fluorine experience higher repulsion among valence electrons, which can slightly reduce the energy released during electron addition.
- This is why chlorine, despite being larger, has a higher electron affinity than fluorine.
Applications in Chemistry:
- Electronegativity is crucial in determining bond polarity and molecular geometry.
- Electron affinity values are used to predict the likelihood of an atom forming negative ions in reactions.