An electron has principal quantum number 2. The number of sub shell and orbitals would be respectively

Options

A. 2 and 3
B. 2 and 5
C. 2 and 7
D. 2 and 4

Explanation

To determine the number of subshells and orbitals for an electron with a principal quantum number of 2, we can follow these steps:

### Step 1: Identify the Principal Quantum Number
The principal quantum number (n) is given as 2. This indicates the energy level or shell in which the electron resides.

### Step 2: Calculate the Number of Subshells
The number of subshells is determined by the azimuthal quantum number (l). The values of l range from 0 to (n-1).

For n = 2:
- The possible values of l are:
- l = 0
- l = 1

These correspond to the subshells:
- l = 0 corresponds to the s subshell
- l = 1 corresponds to the p subshell

Thus, there are **2 subshells** (s and p).

### Step 3: Calculate the Number of Orbitals
The number of orbitals in a given shell can be calculated using the formula n².

For n = 2:
- Number of orbitals = n² = 2² = 4

### Conclusion
Therefore, the number of subshells is 2 and the number of orbitals is 4.

### Final Answer
The number of subshells and orbitals would be **2 subshells and 4 orbitals** respectively.

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