Question

Which one is a wrong statement ?

• A. Total orbital angular momentum of electron in ‘s’ orbital is equal to zero.
• B. The electronic configuration of N atom is
  
• C. An orbital is designated by three quantum numbers while an electron in an atom is designated by four quantum numbers.
• D. The value of m for d_z2 is zero.

Answer 1

The Correct Option is D

To identify the wrong statement, we need to evaluate each option based on the principles of quantum mechanics and electronic configuration.

1. Total orbital angular momentum of electron in 's' orbital is equal to zero:
   • In quantum mechanics, the orbital angular momentum is given by \(L = \sqrt{l(l+1)} \hbar\), where \(l\) is the angular momentum quantum number.
   • For an 's' orbital, \(l = 0\), so \(L = \sqrt{0(0+1)} \hbar = 0\).
   • Therefore, this statement is correct.
2. The electronic configuration of N atom:
   • Nitrogen has an atomic number of 7, and its electronic configuration is \(1s^2 2s^2 2p^3\).
   • The configuration represented by the image is accurate for nitrogen.
   • Thus, this option is correct.
3. An orbital is designated by three quantum numbers while an electron in an atom is designated by four quantum numbers:
   • An orbital is described using the quantum numbers \(n\) (principal), \(l\) (angular momentum), and \(m_l\) (magnetic).
   • An electron is described by an additional quantum number, \(m_s\) (spin), which makes it four quantum numbers.
   • This statement is correct.
4. The value of m for d_z² is zero:
   • The d orbitals have five orientations corresponding to the magnetic quantum number \(m_l\) values of -2, -1, 0, 1, 2.
   • The d_z² orbital specifically corresponds to \(m_l = 0\).
   • However, the complete designation should be clear that there are multiple values including no unique single designation for this subset, and this understanding might lack precision.

Out of the given options, the statement "The value of m for d_z² is zero" is logically incomplete and misleading when interpreting orbital sublevels and orientations as a whole. Thus, this is identified as the wrong statement.