Question

The number of bridged oxygen atoms present in compound B formed from the following reactions is 

\(PB(NO_3)^2→(673 K)→A+PBO+O_2A→(Dimerise)B.\)

• A. 0
• B. 1
• C. 2
• D. 3

Answer 1

The Correct Option is A

To solve this question, we need to understand the chemical transformations involved in the given reactions and identify the bridged oxygen atoms in the resulting compound B.

Let's break down the reactions step-by-step:

1. The initial substance is Pb(NO_3)_2. When it is heated at 673\ K, it decomposes as follows:

Pb(NO_3)_2 \rightarrow PbO + NO_2 + O_2

In this step, lead nitrate decomposes to lead oxide (PbO), nitrogen dioxide (NO_2), and oxygen (O_2).

2. Compound A, likely referred to as a product during this heating process, might be an intermediate containing lead in some lower oxidation state or in a complex form. However, the crucial detail from the problem is that compound A dimerizes to form compound B.

The possible interpretation here is the dimerization involving either an element of the reaction products or unreacted intermediates forming a new structure in B.

3. Dimerization generally suggests two similar units come together. With lead compounds, one could speculate on the formation of structures like peroxides or oxo-bridges, but the question directly asks for "bridged oxygen atoms."

While exam situations might lead to guessing structures involving such intricate bonding, the common lead oxides formed directly from such reactions, even if complex, fundamentally don't include oxygen bridges denoted.

4. Therefore, a complex oxo-structure (like lead oxide) or the mixed lead nitrite intermediates doesn’t apply here, specifically in forming bridged oxygen types.

Thus, the answer is:

Correct Answer: 0 bridged oxygen atoms in compound B are directly implicated from the decomposition and dimerization as described.