If the electron configuration of an element is `1s^(2), 2s^(2), 2p^(6), 3s^(2), 3p^(6), 3d^(2), 4s^(2)`, the four electrons involved in chemical bond formation will be

Options

A. `3p^(6)`
B. `3p^(6), 4s^(2)`
C. `3p^(6), 3d^(2)`
D. `3d^(2), 4s^(2)`

Explanation

To determine the four electrons involved in chemical bond formation for the given electron configuration `1s^(2), 2s^(2), 2p^(6), 3s^(2), 3p^(6), 3d^(2), 4s^(2)`, we can follow these steps:

### Step 1: Identify the Electron Configuration
The electron configuration provided is:
- 1s²
- 2s²
- 2p⁶
- 3s²
- 3p⁶
- 3d²
- 4s²

### Step 2: Determine the Outermost Shell
The outermost shell is the one with the highest principal quantum number (n). In this case, the outermost shell is the 4th shell (4s²), but we also need to consider the 3d subshell because it is partially filled.

### Step 3: Count the Electrons in the Outermost Shell
The electrons in the outermost shell (4th shell) are:
- 4s²: 2 electrons

The electrons in the 3rd shell (which can also participate in bonding) are:
- 3d²: 2 electrons

### Step 4: Total Electrons Involved in Bond Formation
Adding these together, we have:
- 2 electrons from 4s²
- 2 electrons from 3d²

Thus, the total number of electrons involved in chemical bond formation is 2 (from 4s) + 2 (from 3d) = 4 electrons.

### Final Answer:
The four electrons involved in chemical bond formation will be the two electrons from the 4s subshell and the two electrons from the 3d subshell.

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