Which of the following has maximum energy ?

Options

A.
B.
C.
D.

Explanation

To determine which of the given options has the maximum energy, we need to analyze the energy levels of the orbitals involved. The energy order of orbitals is as follows:

1. **s** < **p** < **d** < **f**

This means that the s orbitals have the lowest energy, followed by p, then d, and finally f orbitals have the highest energy.

Now let's evaluate the options provided:

### Step 1: Analyze the options
- **Option A**: 3S (2 electrons), 3P (5 electrons), 3D (0 electrons)
- **Option B**: 3S (3 electrons), 3P (3 electrons), 3D (not applicable)
- **Option C**: 3D (2 electrons)
- **Option D**: 3D (1 electron)

### Step 2: Determine the energy levels
- In **Option A**, the 3S and 3P orbitals are filled, but the 3D orbital has no electrons. Thus, the highest energy orbital here is 3P.
- In **Option B**, the configuration is not possible as you cannot have more than 2 electrons in the 3S orbital.
- In **Option C**, the 3D orbital has 2 electrons. The 3D orbital has higher energy than both the 3S and 3P orbitals.
- In **Option D**, the 3D orbital has only 1 electron, which is still lower in energy compared to the filled 3D orbital in Option C.

### Step 3: Conclusion
Comparing the configurations:
- Option A has electrons in 3S and 3P, but no electrons in 3D.
- Option B is invalid.
- Option C has 2 electrons in 3D, which is the highest energy orbital.
- Option D has only 1 electron in 3D.

Thus, **Option C** has the maximum energy due to the presence of 2 electrons in the 3D orbital.

### Final Answer:
**Option C** has the maximum energy.

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