After filling of `np` orbital, the next orbital filled will be

Options

A. `(n+1)s`
B. `(n+2)p`
C. `(n+1)d `
D. `(n+2)s`

Answer

To determine which orbital is filled after the np orbital, we can follow the order of filling of atomic orbitals based on the Aufbau principle. Here’s a step-by-step solution:

### Step 1: Understand the order of filling orbitals
The order of filling orbitals is determined by their energy levels. The general order of filling is:
1s < 2s < 2p < 3s < 3p < 4s < 3d < 4p < 5s < ...

### Step 2: Identify the np orbital
The np orbital refers to the p orbitals in a given principal quantum number (n). For example:
- 2p (n=2)
- 3p (n=3)
- 4p (n=4)

### Step 3: Determine the next orbital after np
After filling the np orbital, the next orbital that gets filled is the ns orbital, where n is the principal quantum number of the np orbital plus one.

### Step 4: Apply the rule
If we take an example:
- After filling 2p, the next filled orbital is 3s.
- After filling 3p, the next filled orbital is 4s.
- After filling 4p, the next filled orbital is 5s.

### Conclusion
Thus, after filling the np orbital, the next orbital that will be filled is the ns orbital, where n is the principal quantum number of the np orbital plus one.

### Final Answer
The next orbital filled after the np orbital is the (n+1)s orbital.

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