What is the position of the element in the periodic table satisfying the electronic configuration `(n-1)d^1 ns^2` for n = 4?

Options

A. `3^(rd)` period and `3^(rd)` group
B. `4^(rd)` period and `3^(rd)` group
C. `3^(rd)` period and `2^(rd)` group
D. `4^(rd)` period and `2^(rd)` group

Answer

To determine the position of the element in the periodic table with the electronic configuration `(n-1)d^1 ns^2` for `n = 4`, we can follow these steps:

### Step 1: Substitute the value of n
Given the electronic configuration `(n-1)d^1 ns^2`, we substitute `n = 4` into the equation:
- `(4-1)d^1 4s^2`
- This simplifies to `3d^1 4s^2`.

### Step 2: Identify the outer electronic configuration
From the substitution, we find that the outer electronic configuration is `3d^1 4s^2`.

### Step 3: Determine the block of the periodic table
The presence of `d` electrons indicates that this element belongs to the d-block of the periodic table.

### Step 4: Identify the element
The electronic configuration `3d^1 4s^2` corresponds to the element Scandium (Sc), which is the first element in the d-block.

### Step 5: Determine the period and group
- Scandium is located in the 4th period of the periodic table.
- It is also in group 3 (or IIIB in some notations) of the periodic table.

### Conclusion
Thus, the position of the element in the periodic table is:
- **Element**: Scandium (Sc)
- **Period**: 4
- **Group**: 3

### Final Answer
The element with the electronic configuration `(n-1)d^1 ns^2` for `n = 4` is Scandium, which is located in the 4th period and 3rd group of the periodic table.

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