Question

* For the reaction A → Y + Z, the suggested mechanism is A + A + A 1 ks Y + 2 What is the order of the reaction when [A] is very small?

Answer 1

Yt2 A Mechanisma : step • : A+A A+A Z I A K-1 Stefuit : I ke, ytz Applying law of mass action to step (1) к = etup.ua— 12 рет AA) constant 3 [I] =. K [M] - Since rate law for stop (1) + Kzli) = ky x H [n] [by equation is ]] s + de a k' [A] : k'e haki = New constant K-1 k'= kek, A1 = New constant . Thus, order of recution = 1

OH + NO2 - HNO3 Mechanism stepil) : OH + Noz K.(40...NO 2) steplii): (Ho... Non)* kyy OH + NOZ Stefrin) : (HO... Noz)* + Ne kz, HNÜg + Ng On Writing rake is forming law for step (i), as product in Steppi kx [ (60... Now)" ] - + d(HNO3 ] di = Applying steady state approximation for (140 -- 1142) Since steady state approximation is applied for transition stale (T.s.). (HO... NO2)* is a. T.s. of s.s.a can be applied for at d [140. NO2)] = k, [OH ][N02 ] --[40-204] dt = 0 kg (OM3 [NO; } – ka[190.. mos)*] =0 ki [OH] [N0z] k-i [(Ho... Nozjť ]

[6.102]] = tem CH 3 [NUZ ] pulting the value of SCHO.. HU2) * equation (2) in equation (1) ] from 3 + d [HN03] Schedules kex k. [ou] [NO2] » d [HNO3] dt = K [OH] [NO, I Here, k = Kaki = a new S kal Consleent constant . kol Thus, rate of production of HNO3 = + = 2 (2nd order)