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In a multielectron atom, which of the following orbitals described by three quantum numbers have same energy in absence of electric and magnetic fields? A. n = 1, l = 0, m_l = 0 B. n = 2, l = 0, m_l = 0 C. n = 2, l = 1, m_l = 1 D. n = 3, l = 2, m_l = 1 E. n = 3, l = 2, m_l = 0 Choose the correct answer from the options given below :

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

Correct answer: D and E only

Solution

In a multielectron atom, orbitals with the same principal quantum number (n) and the same azimuthal quantum number (l) are degenerate, meaning they have the same energy. Options D and E both have n = 3 and l = 2, making them equal in energy in the absence of external fields.

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