The energy of an electron of `2p_(x)` orbital is :

Options

A. greatern than `2p_(y) `orbital
B. less than `2p_(z)` orbital
C. equal to 2s orbital
D. same as that of `2p_(x) "and" 2p_(z)` orbital

Answer

To determine the energy of an electron in the 2p_x orbital, we need to analyze the quantum numbers associated with the orbital and apply the concept of n + l values.

### Step-by-Step Solution:

1. **Identify the Quantum Numbers:**
- For the 2p_x orbital:
- The principal quantum number (n) is 2.
- The azimuthal quantum number (l) for p orbitals is 1.

2. **Calculate the n + l Value:**
- The n + l value for the 2p_x orbital is calculated as follows:
\[ n + l = 2 + 1 = 3 \]

3. **Calculate n + l for Other Orbitals:**
- For the 2p_y orbital:
- n = 2, l = 1
\[ n + l = 2 + 1 = 3 \]
- For the 2p_z orbital:
- n = 2, l = 1
\[ n + l = 2 + 1 = 3 \]
- For the 2s orbital:
- n = 2, l = 0
\[ n + l = 2 + 0 = 2 \]

4. **Compare n + l Values:**
- The n + l value for 2p_x, 2p_y, and 2p_z orbitals is 3, indicating that these orbitals are degenerate (they have the same energy).
- The n + l value for 2s is 2, which is lower than that of the p orbitals, indicating that the energy of the 2s orbital is lower than that of the 2p orbitals.

5. **Conclusion:**
- Since the n + l values for 2p_x, 2p_y, and 2p_z are the same, the energy of the electron in the 2p_x orbital is the same as that in the 2p_y and 2p_z orbitals.
- Therefore, the correct answer is that the energy of the electron in the 2p_x orbital is equal to that of the 2p_y and 2p_z orbitals.

### Final Answer:
The energy of an electron in the 2p_x orbital is the same as that of the 2p_y and 2p_z orbitals.

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