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explain why the following ground state elec- tron configurations are not possible: (a) 1s22s32p3 (b) 1s22s22p33s6 (c) 1s22s22p73s23p8 (d) 1s22s22p63s23p14s23d14

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Answer:

(a) The electron configuration 1s22s32p3 is not possible because it violates the Pauli exclusion principle, which states that no two electrons in an atom can have the same set of four quantum numbers. The 2p sublevel can hold a maximum of six electrons, with two electrons in each of the three orbitals. Therefore, the 2p sublevel cannot accommodate five electrons as in the given configuration.

(b) The electron configuration 1s22s22p33s6 is not possible because it violates the Aufbau principle, which states that electrons fill orbitals in order of increasing energy, starting from the lowest energy level. The 3s sublevel has a lower energy than the 3p sublevel, so it should be filled before the 3p sublevel. Therefore, the configuration should be 1s22s22p63s2 instead.

(c) The electron configuration 1s22s22p73s23p8 is not possible because it violates the Pauli exclusion principle. The 3p sublevel can hold a maximum of six electrons, with two electrons in each of the three orbitals. Therefore, the 3p sublevel cannot accommodate eight electrons as in the given configuration.

(d) The electron configuration 1s22s22p63s23p14s23d14 is not possible because it violates the Hund's rule, which states that electrons fill orbitals of the same energy level singly, with parallel spins, before they pair up. In the 3d sublevel, the five d orbitals are degenerate (have the same energy). Therefore, the electrons should first fill each of the five d orbitals singly, before pairing up. The correct configuration for this atom should be 1s22s22p63s23p63d54s2 instead.

Step-by-step explanation:

The ground state electron configuration of an atom is the arrangement of electrons in the lowest energy levels available, according to the rules of the Aufbau principle, Pauli exclusion principle, and Hund's rule.

(a) The electron configuration 1s22s32p3 is not possible because it violates the Pauli exclusion principle, which states that no two electrons in an atom can have the same set of four quantum numbers. The 2p sublevel can hold a maximum of six electrons, with two electrons in each of the three orbitals. Therefore, the 2p sublevel cannot accommodate five electrons as in the given configuration.

(b) The electron configuration 1s22s22p33s6 is not possible because it violates the Aufbau principle, which states that electrons fill orbitals in order of increasing energy, starting from the lowest energy level. The 3s sublevel has a lower energy than the 3p sublevel, so it should be filled before the 3p sublevel. Therefore, the configuration should be 1s22s22p63s2 instead.

(c) The electron configuration 1s22s22p73s23p8 is not possible because it violates the Pauli exclusion principle. The 3p sublevel can hold a maximum of six electrons, with two electrons in each of the three orbitals. Therefore, the 3p sublevel cannot accommodate eight electrons as in the given configuration.

(d) The electron configuration 1s22s22p63s23p14s23d14 is not possible because it violates the Hund's rule, which states that electrons fill orbitals of the same energy level singly, with parallel spins, before they pair up. In the 3d sublevel, the five d orbitals are degenerate (have the same energy). Therefore, the electrons should first fill each of the five d orbitals singly, before pairing up. The correct configuration for this atom should be 1s22s22p63s23p63d54s2 instead.

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