Indicate the number of unpaired electrons is
`(i) P (ii) Si (iii) Cr (iv) Fe (v) Kr`.

Explanation

To determine the number of unpaired electrons in the elements phosphorus (P), silicon (Si), chromium (Cr), iron (Fe), and krypton (Kr), we will analyze the electron configurations of each element step by step.

### Step 1: Phosphorus (P)
1. **Electron Count**: Phosphorus has 15 electrons.
2. **Electron Configuration**: The electron configuration is:
- 1s² 2s² 2p⁶ 3s² 3p³
3. **Identifying Unpaired Electrons**:
- In the 3p subshell, there are 3 electrons. Since there are 3 orbitals in the p subshell, each can hold one electron before pairing occurs.
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