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 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 statement is wrong, we will analyze each statement provided in the question step by step.

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

**Analysis:**
- The N-N bond is known to be relatively strong due to the presence of multiple bonds (triple bonds) that nitrogen can form.
- In contrast, the P-P bond is generally weaker because phosphorus can form single bonds more easily and does not have the same multiple bonding capabilities as nitrogen.
- Therefore, this statement is incorrect.

### Step 2: Analyze the second statement
**Statement:** "PH3 acts as a ligand in the formation of coordination compounds with transition elements."

**Analysis:**
- PH3 (phosphine) has a lone pair of electrons on phosphorus, which allows it to donate electrons and act as a ligand.
- This statement is correct.

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

**Analysis:**
- NO2 has an unpaired electron in its molecular structure, which makes it paramagnetic.
- This statement is correct.

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

**Analysis:**
- In N2O5, nitrogen exhibits a covalency of 4 due to its bonding with oxygen atoms.
- This statement is also correct.

### Conclusion
After analyzing all the statements, we find that the first statement is incorrect. Thus, the answer to the question is that the first statement is the wrong one.

### Final Answer:
The wrong statement is: "The single N-N bond is stronger than the single P-P bond."

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