The element having electronic configuration `[Kr] 4d^(10) 4f^(14) 5s^(2) 5p^(6) 5d^(2) 6s^(2)` belongs to

Options

A. s-block
B. p-block
C. d-block
D. f-block

Answer

To determine the block to which the element with the electronic configuration `[Kr] 4d^(10) 4f^(14) 5s^(2) 5p^(6) 5d^(2) 6s^(2)` belongs, we will follow these steps:

### Step 1: Identify the Atomic Number
The electronic configuration can be broken down as follows:
- The configuration starts with `[Kr]`, which corresponds to the atomic number 36.
- Then we have:
- `4d^(10)` contributes 10 electrons.
- `4f^(14)` contributes 14 electrons.
- `5s^(2)` contributes 2 electrons.
- `5p^(6)` contributes 6 electrons.
- `5d^(2)` contributes 2 electrons.
- `6s^(2)` contributes 2 electrons.

Now, let's calculate the total number of electrons:
- Total = 36 (from Kr) + 10 + 14 + 2 + 6 + 2 + 2 = 72

Thus, the atomic number of the element is 72.

### Step 2: Determine the Element
The element with atomic number 72 is Hafnium (Hf).

### Step 3: Determine the Block
To determine the block of the periodic table:
- The last subshell that is being filled in the electronic configuration is `5d^(2)`.
- Elements that have their last filled subshell in the d-block are classified as d-block elements.

### Conclusion
Thus, the element with the electronic configuration `[Kr] 4d^(10) 4f^(14) 5s^(2) 5p^(6) 5d^(2) 6s^(2)` is Hafnium (Hf), and it belongs to the d-block of the periodic table.

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