Question

2 H2 + 2 NO → N2 + 2 H2O the observed rate expression, under some conditions, is: rate = k[NO]2 Which of the following mechanisms are consistent with these data? Select all that are True. step 1 H2 + NO → H2O + N (slow) step 2 N + NO → N2 + O (fast) step 3 O + H2 → H2O (fast)

Answer 1

Step-by-step explanation:

Rate law is defined as the rate of a reaction is directly proportional to the concentration of reactants at constant temperature.

`Rate \propto [\text{concentration of reactant}]^(n)`

= k
`[\text{concentration of reactant}]^(n)`

where, k = rate constant

n = order of reaction

For the given reaction,
`2H_(2) + 2NO \rightarrow N_(2) + 2H_(2)O`

Hence, its rate will be as follows.

Rate =
`k[H_(2)][NO]`

Also, it is known that slowest step in a chemical reaction is the rate determining step.

Hence, for the given rate law correct reaction is as follows.

Step 1 :
`H_(2) + NO \rightarrow N + H_(2)O` (slow)

Balancing this equation it becomes
`H_(2) + 2NO \rightarrow N_(2)O + H_(2)O` (slow)

Step 2:
`N_(2)O + H_(2) \rightarrow N_(2) + H_(2)O` (fast)