Which of the following set of quantum number represent the 19th electr

1.	Which of the following set of quantum number represent the 19th electron in chromium (Z = 24 for Cr)
Answer» 4, 0, 0, `(1)/(2)` 4, 1, `-1, (1)/(2)` 3, 2, 2, `(1)/(2)` 3, 2, `-2, (1)/(2)` Solution :`Cr = 1S^(2) 2S^(2) 2p^(6) 3s^(2) 3p^(6) 3d^(5) 4s^(1)` 19th electron enters 4s because 4s is filled earlier than 3d. For `4s, n = 4, L = 0, m = 0, s = + (1)/(2) or - (1)/(2)`

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