Phosphorous normally exhibits a covalency of _____ and ____ .

Answer

To determine the covalency of phosphorus, we can follow these steps:

### Step 1: Identify the Atomic Number and Electronic Configuration
Phosphorus has an atomic number of 15. Its electronic configuration can be written as:
- 1s² 2s² 2p⁶ 3s² 3p³

### Step 2: Determine the Valence Electrons
The valence electrons of phosphorus are found in the outermost shell (n=3):
- 3s² 3p³
This gives phosphorus a total of 5 valence electrons.

### Step 3: Analyze the Covalency
Covalency refers to the number of bonds an atom can form. Phosphorus can exhibit two main covalent states:
1. **Covalency of +5**: Phosphorus can lose all 5 of its valence electrons to form bonds, resulting in a covalency of +5.
2. **Covalency of -3**: Alternatively, phosphorus can gain 3 electrons to fill its p-orbital (which can hold a maximum of 6 electrons), resulting in a covalency of -3.

### Step 4: Conclusion
Thus, phosphorus normally exhibits a covalency of **-3 and +5**.

### Final Answer:
Phosphorus normally exhibits a covalency of **-3 and +5**.

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