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Correct statements for an element with atomic number 9 are A. There can be 5 electrons for which m_s = +1/2 and 4 electrons for which m_s = -1/2 B. There is only one electron in p_z orbital C. The last electron goes to orbital with n = 2 and l = 1 D. The sum of angular nodes of all the atomic orbitals is 1 Choose the correct answer from the options given below

1. A and B only
2. C and D only
3. A and C only
4. A, C and D only

Correct answer: A, C and D only

Solution

Options A, C, and D are correct because they accurately describe the electron configuration and properties of the element with atomic number 9 (fluorine). A correctly identifies the distribution of spin states among the electrons, C indicates that the last electron fills the 2p orbital, and D correctly states that there is one angular node in the 2p orbital.

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