With reference to periodic table, which of the following does not belong to the set of magic numbers?
Correct answer: C. 20
- A. 8
- B. 18
- C. 20
- D. 32
Explanation
Magic numbers are specific numbers of protons or neutrons in a nucleus, which result in more stable configurations. These numbers are 2, 8, 20, 28, 50, 82, and 126. However, in the context of the periodic table, numbers like 8, 18, and 32 are often noted for their relationship to complete electron shells or subshells, which contribute to an element's chemical stability. Option C (20) does not fit this context as it is not related to the electron configurations that are considered 'magic' in the periodic table, even though it is a magic number in nuclear physics. Therefore, the correct answer is Option C: 20.
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About Periodic Properties and Trends
Periodic properties arise from electron configuration and effective nuclear charge, producing trends in atomic and ionic radius, ionization energy, electron affinity, electronegativity, metallic character and reactivity. Comparisons run across periods and down groups, with attention to common exceptions. The topic also relates these trends to the behavior of s-block and p-block elements.
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