QJEEAdv05Ch9daa: JEE Advanced 2005 Chemistry - Class 11 JEEAdv05Ch9daa Solution: The number of radial nodes of 3s and 2p orbitals are respectively

To find the number of radial nodes in an orbital, we use the formula:

$$\text{Number of radial nodes}=n-l-1$$

where $n$ is the principal quantum number, and $l$ is the azimuthal quantum number (also known as the angular momentum quantum number).

For the 3s orbital:

$n = 3$ (since it is the 3rd energy level) and $l = 0$ (s orbital corresponds to $l = 0$ ).

Plugging these values into the formula gives:

$$\text{Number of radial nodes for 3s}=3-0-1=2$$

For the 2p orbital:

$n = 2$ (since it is the 2nd energy level) and $l = 1$ (p orbital corresponds to $l = 1$ ).

Therefore, the number of radial nodes for the 2p orbital is:

$$\text{Number of radial nodes for 2p}=2-1-1=0$$

Thus, the number of radial nodes of 3s and 2p orbitals are respectively 2 and 0.

Option A is correct: 2, 0