Moderate

For an electron in K-shell, the correct four quantum numbers are represented by;

Correct answer: C. n = 1, l = 0, m = 0, s = +1/2

  • A. n = 2, l = 0, m = 0, s = +1/2
  • B. n = 1, l = 1, m = 0, s = -1/2
  • C. n = 1, l = 0, m = 0, s = +1/2
  • D. n = 1, l = 0, m = 1, s = +1/2

Explanation

The correct four quantum numbers for an electron in the K-shell are:Principal quantum number (n) = 1, which defines the energy level.Azimuthal quantum number (l) = 0, indicating an s orbital.Magnetic quantum number (m) = 0, because an s orbital has no orientation.Spin quantum number (s) = +1/2 or -1/2, representing the two possible spin states of the electron.The principal quantum number (n) for the K-shell is always 1, setting the energy level and proximity to the nucleus. The azimuthal quantum number (l) for an s orbital is 0, determining its spherical shape. The magnetic quantum number (m) is also 0, as there is no spatial orientation for an s orbital. Finally, the spin quantum number (s) can be either +1/2 or -1/2, reflecting the electron's spin direction.Option A is incorrect due to the wrong principal quantum number (n = 2). Option B is incorrect because of the wrong azimuthal quantum number (l = 1). Option D is incorrect due to an incorrect magnetic quantum number (m = 1).

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