Q94 / 180 · AIIMS 2016 · Chemistry

An element $(X)$ belongs to fourth period and fifteenth group of the periodic table. Which one of the following is true regarding the outer electronic configuration of $(X)$ ? It has

  • A
    partially filled $d$ orbitals and completely filled $s$ orbital
  • B
    completely filled $s$ orbital and completely filled $p$ orbitals
  • Correct answer
    C
    completely filled $s$ orbital and half-filled $p$ orbitals
  • D
    half-filled $d$ orbitals and completely filled $s$ orbital.

Solution

The electronic configuration of $(X)$ can be written as $X=1 s^2 2 s^2 2 p^6 3 s^2 3 p^6 4 s^2 3 d^{10} 4 p^3$ So, element $(X)$ has completely filled $s$ and $d$ orbitals and half filled $p$ orbitals.

Hence, the correct answer is option: 'C'.

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