Which of the following statements is wrong ?

Options

A. Single N-N bond is stronger than the single P-P bond.
B. `PH_(3)` can act as a ligand in the formation of coordination compound with transition elements.
C. `NO_(2)` is paramagnetic in nature.
D. Covalency of nitrogen in `N_(2)O_(5)` is four.

Explanation

To determine which of the given statements is wrong, we will analyze each statement one by one.

### Step 1: Analyze the first statement
**Statement:** "Single N-N bond is stronger than the single P-P bond."

- **Analysis:**
- The N-N bond involves two nitrogen atoms, each having 5 valence electrons. When they form a single bond, they also have lone pairs that can lead to electron-electron repulsion due to their small size.
- The P-P bond involves larger phosphorus atoms, which have more space and can accommodate lone pairs better, leading to less repulsion.
- Therefore, the N-N bond is weaker than the P-P bond due to the higher electron repulsion in nitrogen.

**Conclusion:** This statement is **wrong**.

### Step 2: Analyze the second statement
**Statement:** "pH3 can act as a ligand in the formation of coordination compound with transition elements."

- **Analysis:**
- pH3 (phosphine) is known to act as a ligand because it has a lone pair of electrons on phosphorus that can coordinate with transition metals.

**Conclusion:** This statement is **correct**.

### Step 3: Analyze the third statement
**Statement:** "NO2 is paramagnetic in nature."

- **Analysis:**
- NO2 has an odd number of electrons (11 electrons), which means it has unpaired electrons. This gives it paramagnetic properties.

**Conclusion:** This statement is **correct**.

### Step 4: Analyze the fourth statement
**Statement:** "Covalency of Nitrogen in N2O5 is 4."

- **Analysis:**
- In N2O5, nitrogen forms double bonds with oxygen and also has coordinate bonds. Each nitrogen atom forms four bonds in total (two double bonds and two coordinate bonds).

**Conclusion:** This statement is **correct**.

### Final Conclusion
The only statement that is wrong is the first one: "Single N-N bond is stronger than the single P-P bond."

Thus, the correct answer is **option A**.

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