Rank the following elements in order of increasing electron affinity: Cs, Hg, F, S

• A. Hg < S < F < Cs
• B. Hg < F < S < Cs
• C. Cs < S < F < Hg
• D. Hg < Cs < S < F
• E. Cs < Hg < S < F

Answer: (D)

Verified step by step guidance

1. Understand the concept of electron affinity: Electron affinity is the amount of energy released when an electron is added to a neutral atom in the gaseous state. Generally, elements with higher electron affinity are more likely to gain electrons.
2. Consider the periodic trends: Electron affinity generally increases across a period from left to right and decreases down a group in the periodic table. This is because atoms on the right side of the periodic table have more protons, attracting electrons more strongly.
3. Analyze the given elements: Cs (Cesium) is in Group 1, Hg (Mercury) is in Group 12, S (Sulfur) is in Group 16, and F (Fluorine) is in Group 17. Fluorine, being in Group 17, typically has the highest electron affinity due to its high electronegativity.
4. Compare the elements based on their positions: Cs is at the bottom of Group 1, so it has a low electron affinity. Hg is a transition metal and generally has lower electron affinity compared to nonmetals. S and F are nonmetals, with F having the highest electron affinity.
5. Rank the elements: Based on the periodic trends and positions, the order of increasing electron affinity is Hg < Cs < S < F. This means Mercury has the lowest electron affinity, followed by Cesium, then Sulfur, and Fluorine has the highest.