Answer:
k * [H2]*[NO]²
Explanation:
2NO(g) + 2H2 (g) → N2 (g) + 2H2O (g)
Rate law = k*[A]^x *[B]^y
with k = rate constant
with [A] = concentration of A
with [B] = concentration of B
x and y are the orders of A and B respectively.
Rate is defined as: decrease in the concentration of reactants / time
For the given reaction:
⇒first order in H2 ⇔ rate α = [H2]∧1
⇒second order in NO ⇔ rate α = [NO]²
Rate law:
⇒then x =order of A = 1
⇒then y = order of B = 2
⇒Total order 1+2 =3 ⇒ third order