Question

Identify the order of following reaction: $2\text{NO}_{2}(g)\rightarrow2\text{NO}(g)+\text{O}_{2}(g)$.

• A. 1
• B. 1.5
• C. 2
• D. 3

Hint:

While order is an experimental fact, textbook examples are fixed.
$2\text{N}_2\text{O}_5 \rightarrow 4\text{NO}_2 + \text{O}_2$ is First Order.
$2\text{NO}_2 \rightarrow 2\text{NO} + \text{O}_2$ is Second Order.

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
The order of a reaction is an experimentally determined quantity that represents the power to which the concentration of a reactant is raised in the rate law.

Step 2: Formula Application:
For the thermal decomposition of Nitrogen dioxide ($NO_2$), the rate law is found experimentally to be $Rate = k[NO_2]^2$.

Step 3: Explanation:
The reaction involves the collision of two $NO_2$ molecules. Since the rate depends on the square of the $NO_2$ concentration, the overall order of the reaction is 2.

Step 4: Final Answer:
The order of the reaction is 2.