Here are the essential concepts you must grasp in order to answer the question correctly.
Atomic Radius
Atomic radius refers to the size of an atom, typically measured from the nucleus to the outermost electron shell. As you move down a group in the periodic table, atomic radius increases due to the addition of electron shells, which outweighs the increase in nuclear charge. Therefore, sulfur (S), being below oxygen (O) in the periodic table, has a larger atomic radius.
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Electronegativity
Electronegativity is a measure of an atom's ability to attract and hold onto electrons in a chemical bond. It generally increases across a period from left to right and decreases down a group. Oxygen, being higher in the periodic table than sulfur, has a greater electronegativity, meaning it is more effective at attracting electrons compared to sulfur.
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Periodic Trends
Periodic trends are patterns observed in the periodic table that describe how certain properties of elements change across periods and down groups. Key trends include atomic radius, electronegativity, ionization energy, and electron affinity. Understanding these trends helps predict the behavior of elements, such as why oxygen is more electronegative than sulfur and why sulfur has a larger atomic radius.
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