Chemistry Atomic Structure NUMS 2024
PMDC Verified Question 21 of 95
Choose the allowed sets of quantum numbers from the following:
A
\( n = 3, l = 2, m = 0, s = +1/2 \)
B
\( n = 3, l = 3, m = 0, s = -1/2 \)
C
\( n = 4, l = 3, m = 4, s = +1/2 \)
D
\( n = 4, l = 2, m = 4, s = -1/2 \)
Tap any option to test your recall and reveal the step-by-step Propolis autopsy.

Propolis Cognitive Error Autopsy

Official Correct Choice:
Option A: \( n = 3, l = 2, m = 0, s = +1/2 \)
Concept: The validity of a set of quantum numbers depends on strict boundary rules connecting \( n, l \), and \( m \).

Formula: $$ l = 0 \text{ to } (n-1) $$ $$ m = -l \text{ to } +l $$

Solution:
  • Let's evaluate each option to see if it breaks any rules:
  • Option A: \( n=3 \). Max \( l = 2 \). So \( l=2 \) is allowed. If \( l=2 \), \( m \) can be from -2 to +2. So \( m=0 \) is allowed. Spin is +1/2. This set is perfectly valid.
  • Option B: \( n=3 \). Max \( l = 3-1 = 2 \). Here \( l=3 \), which violates the rule (\( l \) cannot equal \( n \)). Invalid.
  • Option C: \( n=4 \), \( l=3 \) is allowed. However, if \( l=3 \), the max value of \( m \) is +3. Here \( m=4 \) is given, which violates the rule. Invalid.
  • Option D: \( n=4 \), \( l=2 \) is allowed. If \( l=2 \), max \( m \) is +2. Here \( m=4 \) is given, which violates the rule. Invalid.


Why other options are incorrect: Options B, C, and D mathematically violate the restrictive boundary rules of quantum mechanics.

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