Problem 14 - 43 Years JEE ADVANCED (1978-2020) + JEE MAIN Chapterwise & Topicwise Solved Papers Chemistry

Question

The number of P \(-\mathrm{O}\) bonds in \(\mathrm{P}_{4} \mathrm{O}_{6}\) is: [Main Online April 15, \(\mathbf{2 0 1 8}\) (II)] (a) 9 (b) 6 (c) 12 (d) 18

Step-by-Step Solution

Answer

The number of P-O bonds in \( \text{P}_4\text{O}_6 \) is 12.

Step 1: Understanding the Chemical Formula

The formula \( \text{P}_4\text{O}_6 \) represents a molecule consisting of 4 phosphorus (P) atoms and 6 oxygen (O) atoms. This is a compound known as tetraphosphorus hexoxide.

Step 2: Drawing the Lewis Structure

To visualize the bonds, draw the Lewis structure of \( \text{P}_4\text{O}_6 \). In this structure, each phosphorus atom is connected to three oxygen atoms, and one oxygen atom connects two phosphorus atoms.

Step 3: Counting P-O Bonds

In the Lewis structure of \( \text{P}_4\text{O}_6 \), we observe each phosphorus atom forms bonds with the oxygen atoms. There are a total of 6 P-O-P connections (bridging) and 6 P=O bonds (double bonds), totaling to 12 P-O bonds.

Step 4: Verifying with Structure

Confirm using the Lewis structure, which shows 4 phosphorus atoms forming a tetrahedral arrangement with oxygen atoms acting as bridges and terminal atoms. This validates the 12 P-O bonds determined earlier.

Key Concepts

Lewis structure

To grasp the concept of bonding in phosphorus oxide molecules like \( \text{P}_4\text{O}_6 \), we first need to understand how to draw the Lewis structure. Lewis structures are diagrams that show the bonding between atoms as well as the lone pairs of electrons that may exist in the molecule. They are crucial in predicting the geometric arrangement of molecules.

When constructing the Lewis structure for \( \text{P}_4\text{O}_6 \), we focus on how each phosphorus atom is linked to oxygen atoms. In this compound:

• Each phosphorus atom is connected to three oxygen atoms.
• One of these oxygen atoms serves as a bridge, connecting two phosphorus atoms.
• Through these connections, the structure depicts both single and double bonds.

The depiction of bonds and electron pairs helps us understand the molecular structure and chemical properties, which is imperative when dealing with compounds like phosphorus oxide.

phosphorus oxide

Phosphorus oxide is a term that refers to a group of compounds formed with phosphorus and oxygen. Specifically, \( \text{P}_4\text{O}_6 \) is known as tetraphosphorus hexoxide. When naming these oxides, it is essential to consider the ratio of phosphorus to oxygen, as this dictates their chemical properties and how they behave in reactions.

The compound \( \text{P}_4\text{O}_6 \) is characterized by a tetrahedral arrangement of phosphorus atoms surrounded by oxygen atoms. This makes it a classic example for studying chemical bonding and molecular geometry. The connectivity in phosphorus oxide involves a combination of:

• Single bonds, where phosphorus atoms are directly linked to oxygen.
• Bridging oxygen atoms that connect neighboring phosphorus atoms.
• Double bonds, adding complexity to the structure and affecting the molecule's reactivity.

The unique structure of phosphorus oxide molecules plays a significant role in their potential applications and reactivity in both industrial and laboratory settings.

bond counting

Bond counting is a critical skill in chemistry, especially when analyzing complex molecules like \( \text{P}_4\text{O}_6 \). It involves determining the total number of bonds within a molecule. This exercise can reveal insights into molecular stability, reactivity, and energy.To count bonds in the \( \text{P}_4\text{O}_6 \):

• Identify each phosphorus atom is involved in multiple bonds with oxygen atoms.
• There are 6 P-O-P links, where an oxygen atom bridges two phosphorus atoms. This counts as single bonds between phosphorus and oxygen.
• Additionally, there are 6 P=O bonds, involving double bonds within the same molecule.
• Adding both the number of single and double bonds results in a total of 12 P-O bonds.

Careful inspection of the Lewis structure allows us to verify these bonds, confirming the molecule's complexity. Understanding bond counting provides deeper comprehension of the molecule's geometry and how it might behave under various conditions.