Question

In the antibonding molecular orbital, there is a point between the two probability contours of the hydrogen atom. This is called:
A.Node
B.Antinode
C.A plane where electron charge density is maximum
D.A and C both are correct

Answer 1

Hint:Node: A plane where the probability to find the electron i.e. electron density is zero in an orbital. There are two types of nodes: angular nodes and radial nodes.
Antinode: A plane where the probability to find the electron i.e. electron density is maximum in an orbital.

Complete step by step answer:
First of all we will discuss molecular bonding and antibonding orbitals.
Atomic Orbitals: The place where electrons are found in an atom, is known as orbitals.
Just like atomic orbitals when atoms linked with each other to form molecules they have molecular orbitals. There are two types of orbitals in molecules: bonding and antibonding.
Bonding molecular orbitals: When atoms are linked to each other then the orbitals which result due to in-phase combinations of atomic waves, are known as bonding molecular orbitals. They have less energy so they are more stable.
Anti-Bonding molecular orbitals: When atoms are linked to each other then the orbitals which result due to out-phase combinations of atomic waves, are known as anti-bonding molecular orbitals. They have more energy so they are less stable. While forming a molecule first electrons go to the bonding molecular orbital then the electrons go into the antibonding orbitals.
Principle quantum number: It is defined as the quantum number which describes the electron’s state. It is represented by $n$. It’s value starts from $1$.
Azimuthal quantum number: It is defined as a quantum number which describes the shape of the orbital and its orbital angular momentum. It is represented by $l$. It’s value is from $0$ to $(n - 1)$.For $s$ ,$l = 0$ for $p{\text{ ,l}} = 1$ and so on.
Node: A plane where the probability to find the electron i.e. electron density is zero in an orbital. There are two types of nodes: angular nodes and radial nodes.
Radial node: The surface where the probability of finding the electrons is zero. The number of radial nodes is $(n - l - 1)$ where $n$ is principal quantum number and $l$ is azimuthal quantum number.
Angular node: The plane where the probability of finding the electrons are zero. The number of angular nodes is equal to the azimuthal quantum number i.e. number of angular nodes is equal to $l$.
Antinode: A plane where the probability to find the electron i.e. electron density is maximum in an orbital.
So in the antibonding molecular orbital, there is a point between the two probability contours of the hydrogen atom. This is called a node.
Hence option A is correct.

Note: Quantum number: These are defined as the number which completely describes the position of electrons in an atom. There are four quantum numbers: principal, azimuthal, magnetic and spin quantum numbers.