更新1:
=.=第壹位人兄
妳同無答過有咩分別 而家就系問妳點判斷丫MA 第二位人兄
問題就系佢比的REACTANT 唔系ORGANIC CHEM學果D 系INORGANIC的REACTANT 甚至系UNKNOWN的REACTANT但系就要妳估佢系咪SINGLE STEP 所以除左SN1
SN2之外 請提出其他判斷方法...thx
更新2:
問題壹: X(g)+Y(g)-->XY(g) *X
Y are unknown elements. It's rate equation : rate=k[X(g)][Y(g)]^2 問題: Can it be a single stage reaction?Explain your wer. 資料就得咁多....根據咩野判斷佢系定唔系丫?
更新3:
問題二: 2I(g)--> I2(g) (in presence of argon) rate=k[I]^2[Ar] 問題: Suggest a possible reaction mechani *** consistent with the rate equation
state the role of argon
and sketch the energy profile 我完全唔知點樣估
點樣睇得出佢有無intermediate仲要估埋系咩野丫?
更新4:
問題三: A+B-->product rate = k[A] 問題:sketch a possible energy profile. 點知佢系multi-step嫁? 總括而言我凈系想有人話我知點樣判斷 例如凡系點樣就會系single....又或者先睇邊樣再睇邊樣咁 各位幫幫忙啦~我好唔明白究竟點樣判斷 *第二同埋第三條來自零壹同埋九九年的PASTPAPER
問題壹： 由rate equation睇，壹定唔系single stage 如果系single stage既話，X(g) + Y(g) --> XY(g)本身就系rate deterimining step， 寫出黎既rate equation應該系rate=k[X(g)][Y(g)] 如果要寫出rate=k[X(g)][Y(g)]^2， rate deterimining step壹定要系X(g) + 2Y(g) --> product 偶唔記得AL有冇教過，但系rate equation既order = rate deterimining step既reactant coefficient eg：X --> product rate=k[X] 2X --> product rate=k[X]^2 X + Y --> product rate=k[X][Y] 2X + Y --> product rate=k[X]^2[Y] 2X + 2Y --> product rate=k[X]^2[Y]^2 註意左邊既系rate deterimining step，唔系overall equation 問題二： Possible reaction mechani *** 可能系 1) 2I-(g) + Ar(g) --> I2Ar(g) Slow（其實系I定I-？） 2) I2Ar(g) --> I2(g) + Ar(g) Fast 其實妳可以隨意寫，只要d step加埋得番出條overall equation， 同埋consistent with the rate equation，即系 2I-(g) + Ar(g) --> I2Ar(g) rate=k[I-]^2[Ar] （2X + Y --> product rate=k[X]^2[Y]） Ar應該系intermediate， energy profile麻煩閣下勞動壹下玉手，偶最討厭畫graph……=_= 問題三： 要知系唔系multi-step，請睇rate equation 因為rate = k[A]，所以rate deterimining step系 A --> product 唔match妳條overall equation， 所以壹定系muti-step 至於energy profile……同上 : ) 要判斷既話只要睇rate equation同overall equation match唔match到就得 再唔明可以email問偶，同樣id不過請用hotmail （yahoo偶十世都唔check……） PS. 死小電妳想同偶Hang幾次機！？同壹篇Ans偶打左3次！3次！可．怒．也！+皿+ 2008-04-14 10:34:20 補充： 個d "-->" 其實系"→"，唔知點解全部亂碼左……=_= 2008-04-14 14:43:01 補充： 更正！ Ar應該系catalyst至啱！
參考: 區區在下偶～
You'd better write down the actual equation and rate equation. Normally from the rate equation
you could only know which reactant or intermediate involving in the rate determining step. If you pare it with the chemical equation
then you may work out whether it is single or multi step reaction. If the original reactants appear in the rate equation
we coudl say it is a single step reaction.If intermediate is involved
it must be a multistep reaction.
睇返佢系SN1定系SN2 同埋睇條mechani *** 本身.. 2008-04-10 02:03:46 補充： 妳不如講個例子出黎 我先知妳邊度唔明=.= 睇到條equation就自然會知 :( 好少何會就咁問嫁下話=.=? 問親呢d都系做exp
有個表
妳填哂 跟住用計返個rate equation出黎 自然就會知道邊只系k[A]^x[B]^y =rate 咁上下既野.. 咁妳就可以用佢黎support which reactants exist in the rds.
If you know the rate equation of a reaction (if fact
you know the equation of the reaction)
you must firstly proposed a mechani *** for the reaction before you draw the energy profile. This is because energy profile is the graphical representation for the potential energies of the reactant(s)
product(s)
intermediate(s) and trition state(s). All these substances are included in the reaction mechani *** . You can only draw the energy profile according the mechani *** of the reaction. Furthermore
if the proposed mechani *** is incorrect
the corresponding energy profile would bee meaningless.