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chem cie p4 nid help to explain pls ^^

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guowie88:
i don't understand the part b]

Deadly_king:

--- Quote from: guowie88 on November 08, 2010, 03:43:33 pm ---i don't understand the part b]

--- End quote ---

2.(b) Given rate= k[H2O2]a[I-]b[H+]c

a represents the order of reaction with respect to [H2O2].
b represents the order of reaction with respect to [I-].
c represents the order of reaction with respect to [H+].

NOTE : 1. The slowest step is the rate determining step.
           2. The number of moles of a reactant in the rate determining step gives the order with respect to that of the reactant.

When step 1 is slowest overall : a=1, b=1 and c=0
This is because in step 1, the number of moles of H2O2 is 1 and so is I-. However H+ is not present in this equation which means it has order zero.(Reaction is independent of H+)

When step 2 is slowest overall: a=1, b=1 and c=1
IO- is formed from H2O2 and I-. Replace the first equation in the second and you'll get :
H2O2 + I- + H+ ---> HOI + H2O
From this equation, note the number of moles of the respective reactants.

When step 3 is slowest overall : a=1, b=2 and c=2.
Replace the new equation found above in this third step and you'll get :
H2O2 + 2I- + 2H+ ---> I2 + 2H2O
From this equation, note the number of moles of the respective reactants.

I sincerely hope my explanations are clear enough for you to understand. :)

guowie88:
Thk totally understand now ^^
juz like math subsitution XD

Deadly_king:

--- Quote from: guowie88 on November 09, 2010, 05:33:45 am ---Thk totally understand now ^^
juz like math subsitution XD

--- End quote ---

Yupz......same to same. ;)

Glad that you understood :)

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