Question

The number of nodal planes in ${}^\sigma 2{p_x}$ molecular orbital is
A. 0
B.1
C.3
D.2

Answer 1

In all the three p- orbitals, two dumb bell shape lobes are present which are parted from each other by a point where the probability of getting the electron is zero. This point is known as the nodal plane. The nodal plane is related to the azimuthal quantum number.

Complete step by step answer:
A plane passing through the nucleus where the chance of finding the electron is zero is called a nodal plane. The nodal plane is also known as angular node.
The number of nodal planes is determined by the azimuthal quantum number.
The azimuthal quantum number is one of the sets of quantum numbers which helps to determine the state of the electron.
The azimuthal quantum number is denoted by $l$. This number helps to describe the orbital shape and also the orbital angular momentum. The azimuthal quantum number value varies from 0 to n-1.
For s-orbital, azimuthal quantum number is 0.
For p-orbital, azimuthal quantum number is 1.
For d-orbital, azimuthal quantum number is 2.
For f-orbital, azimuthal quantum number is 3.
The given molecular orbital is ${}^\sigma 2{p_x}$.
Hence, for p orbital the azimuthal quantum number is equal to 1.
Thus the nodal plane of the ${}^\sigma 2{p_x}$ orbital is equal to 1.
Therefore, the correct option is B.

Note:
In the three p- orbital ${p_x}$,${p_y}$ and ${p_z}$ have equal energy and shows same relation with the nucleus but the all three orbitals differ from each other in their direction and charge distribution. All the three orbitals are located at right angles with one another and directed towards the x-axis, y-axis and z-axis.