Answer the question on the basis of passage given below:

Second period elements of p-Block differ from the rest of their group members due to their small atomic size, high electronegativity, high ionization enthalpy and absence of d-orbitals.

The elements from the second period like C, N, O have unique property of forming pa pa multiple bonds whereas other heavier elements of p-block form da pa multiple bonds. This changes the properties of second period elements to great extent. Also the single bond strength of the p-block elements with their own atoms gets affected by their atomic size and presence of lone pairs.

Inert pair effect also affects the properties of the p-Block elements especially for those elements which are present from 4th period onward and this happens due to poor screening effect of inner (n-1) d subshell electrons.

Catenation tendency of Nitrogen is weaker than Phosphorus, because

\(N-N\) bond strength is weaker than \(P-P\) bond strength

The correct answer is option 3. \(N-N\) bond strength is weaker than \(P-P\) bond strength. 

Nitrogen atoms can form a triple bond with each other, resulting in a very strong bond between the nitrogen atoms in a nitrogen molecule (\(N_2\)). This triple bond consists of one sigma (\(\sigma\)) bond and two pi (\(\pi\)) bonds. The presence of these multiple bonds, particularly the pi bonds, contributes to the overall strength of the \(N-N\) bond in nitrogen molecules.

Phosphorus atoms can form single bonds with each other, resulting in a bond between phosphorus atoms in a phosphorus molecule (\(P_4\)). These single bonds, known as \(P-P\) single bonds, are generally weaker than the triple bond in nitrogen. This is because the triple bond in nitrogen involves more shared electrons and a higher degree of orbital overlap, leading to a stronger bond.

Catenation refers to the ability of an element to form bonds with itself, resulting in the formation of long chains or rings. In the context of nitrogen and phosphorus, catenation tendency is influenced by the strength of the bonds between the atoms of each element.

The stronger triple bond between nitrogen atoms makes it difficult for nitrogen molecules to break apart and form longer chains or rings. In contrast, the weaker single bonds between phosphorus atoms allow phosphorus molecules to more readily break apart and form longer chains or rings.

Because the \(N-N\) bond strength is stronger than the \(P-P\) bond strength, nitrogen has a weaker catenation tendency compared to phosphorus. This means that nitrogen atoms are less likely to form long chains or rings compared to phosphorus atoms, which can readily form such structures due to the weaker bonds between them.

In summary, the weaker \(N-N\) bond strength compared to the \(P-P\) bond strength contributes to nitrogen's weaker catenation tendency compared to phosphorus.