Question

Consider the following reaction:

2NO(g)+2H₂(g) => N₂(g)+2H₂O(g).
The rate law for this reaction is first order in H2 and second order in NO.
Write the rate law:

1. rate= k[H₂][NO]
2. rate= k[H₂][NO]²
3. rate= k[H₂]²[NO]
4. rate= k[H₂]

Answer 1

The rate law for the reaction 2NO(g) + 2H₂(g) ⇒ N₂(g) + 2H₂O(g) when it's first order in H₂ and second order in NO is rate = k[NO]²[H₂], which makes the reaction third order overall.

Step-by-step explanation:

The rate law for the reaction 2NO(g) + 2H₂(g) ⇒ N₂(g) + 2H₂O(g) can be determined based on the information given. If the reaction is first order with respect to H₂ and second order with respect to NO, then the rate law for the reaction is rate = k[NO]²[H₂], indicating that the reaction rate is directly proportional to the square of the concentration of NO and to the concentration of H₂. Thus, the correct rate law is the second option: rate = k[H₂][NO]². The reaction is said to be first order in H₂ and second order in NO, which makes the overall reaction order third order (1 for H₂ + 2 for NO).