Which of the following is not a possible value of azimuthal quantum number (I) for an electron with n = 3?

Options

A. zero
B. 1
C. 2
D. 3

Answer

To determine which of the following is not a possible value of the azimuthal quantum number (l) for an electron with n = 3, we can follow these steps:

### Step 1: Understand the Principal Quantum Number (n)
The principal quantum number (n) indicates the energy level of an electron in an atom. In this case, we are given that n = 3.

### Step 2: Determine the Possible Values of the Azimuthal Quantum Number (l)
The azimuthal quantum number (l) can take on values ranging from 0 to (n - 1). Therefore, for n = 3:
- The possible values of l are:
- l = 0 (s orbital)
- l = 1 (p orbital)
- l = 2 (d orbital)

### Step 3: Identify the Values of l
From Step 2, we have:
- l = 0 (s)
- l = 1 (p)
- l = 2 (d)

### Step 4: Identify the Non-Possible Value
Since l can only take values from 0 to 2 for n = 3, any value greater than 2 is not possible. Therefore, l = 3 is not a valid value for the azimuthal quantum number when n = 3.

### Conclusion
The value that is not a possible value of the azimuthal quantum number (l) for an electron with n = 3 is **3**.