Step 1: Understanding the Concept:
The Modern Periodic Table organizes elements into vertical columns called "Groups" based on their valence shell electronic configurations. Elements in the same group exhibit similar chemical properties because they have the same number of electrons in their outermost shell. Group 16 is collectively known as the "Chalcogens" or the "Oxygen family." All elements in this group have six valence electrons, with the general electronic configuration \(ns^{2} np^{4}\). This family includes both non-metals (Oxygen, Sulfur), metalloids (Selenium, Tellurium), and metals (Polonium). Identifying which element does not belong requires a basic knowledge of the periodic positions of common elements.
Step 2: Detailed Explanation:
Let's examine the members of the families involved in the options:
Members of Group 16 (Chalcogens):
1. Oxygen (O): Atomic number 8. Configuration: \([He] 2s^{2} 2p^{4}\). It is the first member of Group 16.
2. Sulfur (S): Atomic number 16. Configuration: \([Ne] 3s^{2} 3p^{4}\). It is the second member of Group 16.
3. Selenium (Se): Atomic number 34. Configuration: \([Ar] 3d^{10} 4s^{2} 4p^{4}\). It is the third member of Group 16.
4. Tellurium (Te): Atomic number 52. Fourth member.
5. Polonium (Po): Atomic number 84. Fifth member.
Now let's look at the outlier:
Chlorine (Cl): Chlorine has an atomic number of 17. Its electronic configuration is \([Ne] 3s^{2} 3p^{5}\). Since it has seven valence electrons (one more than sulfur), it belongs to Group 17. Group 17 elements are known as the "Halogens." This family includes Fluorine, Chlorine, Bromine, Iodine, and Astatine.
Step 3: Comparison and Conclusion:
Options (1), (2), and (3) - Oxygen, Sulfur, and Selenium - are all consecutive members of the same vertical column (Group 16). They all share the \(p^{4}\) valence subshell configuration. Chlorine, however, is located one step to the right in the periodic table, placing it in the \(p^{5}\) column. Therefore, it is chemically and structurally distinct from the Chalcogen family.
Step 4: Final Answer:
Chlorine does not belong to Group 16; it is a Group 17 element.
Hence, the correct answer is option (4).