



The bond line formula for a compound is a simplified representation of its molecular structure without showing individual hydrogen atoms attached to carbon atoms. It provides a clearer depiction of the backbone structure made by carbon atoms and any functional groups or substituents.
The given compound is HOCH(CN)2, which can be expanded to show:
To determine the correct bond line structure:
The correct bond line structure will show a central carbon atom with lines representing the bonds to the hydroxyl and cyano groups. Let's examine the options:
Therefore, the correct bond line formula is as represented in Fig 4.
This formula accurately depicts the structure as:
Hence, the answer is correctly represented by Fig 4.
The given compound is \( \text{HOCH(CN)}_2 \). This indicates a carbon atom bonded to a hydroxyl group (\(-\text{OH}\)) and two cyano groups (\(-\text{CN}\)).
The correct bond-line formula for this structure is represented by option (4).
Explanation: The central carbon atom is bonded to one hydroxyl group (\(-\text{OH}\)) and two cyano groups (\(-\text{CN}\)). This structure matches the representation of option (4), showing two cyano groups attached to the central carbon atom along with the hydroxyl group.
Match List-I with List-II: List-I
The correct increasing order of stability of the complexes based on \( \Delta \) value is:

The equivalent resistance between the points \(A\) and \(B\) in the given circuit is \[ \frac{x}{5}\,\Omega. \] Find the value of \(x\). 
Method used for separation of mixture of products (B and C) obtained in the following reaction is: 
In the following \(p\text{–}V\) diagram, the equation of state along the curved path is given by \[ (V-2)^2 = 4ap, \] where \(a\) is a constant. The total work done in the closed path is: 
Let \( ABC \) be a triangle. Consider four points \( p_1, p_2, p_3, p_4 \) on the side \( AB \), five points \( p_5, p_6, p_7, p_8, p_9 \) on the side \( BC \), and four points \( p_{10}, p_{11}, p_{12}, p_{13} \) on the side \( AC \). None of these points is a vertex of the triangle \( ABC \). Then the total number of pentagons that can be formed by taking all the vertices from the points \( p_1, p_2, \ldots, p_{13} \) is ___________.