Mechanisms and Molecularity understand how elementary steps make up a how the la
ID: 488609 • Letter: M
Question
Mechanisms and Molecularity understand how elementary steps make up a how the law for an elementary step can be determined Wery chen, a reaction does not tell us the whole story. For instance, the reaction does not involve a colision between an NOh moleoule and aco molecule, Based on experimental data at moderate tempertures. this reaction isthought to occurin the folowing 1.NO (s) +NO (s)- Nos (g) NO(g) Each individual step is called an elemerwary Together, these elementary steps are called the reaction mechansm Overall, the renuing reaction NO, (g) +co(g) NO(g) +co (g) Notice eat in elemantay steps NOs appears both as a product and as a reactant, therefore it cancels out of mal chemical quation Noh is called NOh appear in the reactants NOh appears as product of the the step and 1 molecule second step, the net efect leaves only 1 molecule of Noh as a reactant in the net equation. is the proper tem for how moleoules oolide in reaction. For example, step 1 is bimolecular because t involves the colision of two molecules step 2is also bimolecular for the same reason imolecular reactions involve only ene molecule inthe reactants. Though rare, collisions among three moleoules Order and rate law of a reaction The overal order of an elementary step directly oomesponds molecularly. Both steps in this example are seoond onder because they are each bimolecular. Furthermore the rate law can be determined dinectly from the number of each type of moleoule in an elementary step For example, the rate law for step 1 is rate KNO, The exponent 2 used because the reaction involves heeNO, molecules. The rate law for step 2 is because the reaction involves only one molecule of each madtant the exponents are ammited. Consider the following elementary steps that make up the medhanism of a certain reaction Part A What is the overal reaction? Express your answer as a chemical equation. Submit My An werv Give up Revie Pers Part B
Explanation / Answer
A. Adding equations 1 and 2 gives the overall reaction which is, 3X + M -----> 2F + N
B. E is the intermediate.
C. Rate = k [X]3
D. Rate = k [E] [M]