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Topic: Rates of Chemical Reaction  (Read 5062 times)

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sci0x

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Rates of Chemical Reaction
« on: January 28, 2006, 09:24:54 AM »
Quick Question:

The formula for rate = k (reactant)^a [reactant]^b [reactant]^c

Now i do three experiments with

Experiment 1:
0.8mL Water,
0.8mL 2-butanol, 2M
0.8mL Sulfuric Acid, 1M
0.8mL Potassium Permanganate, 0.2M

Experiment 2:
All the same only I have 0.4mL Potassium Permanganate

Experiment 3:
All the same only I use 0.2mL Potassium Permanganate

Now I have to calculate the rate for each experiment:

So for experiment 1 is the rate:
k (reactant)^a [reactant]^b [reactant]^c

(0.8ml KMnO4)[2M 2-butanol][1M Sulfuric Acid]
= 1.6

But what values do I use for k and the exponents a, b and c?

« Last Edit: January 28, 2006, 09:26:32 AM by sci0x »

Offline plu

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Re:Rates of Chemical Reaction
« Reply #1 on: January 28, 2006, 10:11:24 AM »
You can only find the rate of the reaction through experiment.  (i.e. indicators and a stopwatch)

sci0x

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Re:Rates of Chemical Reaction
« Reply #2 on: January 28, 2006, 10:18:06 AM »
What about using time vs absorbance. I have graphs made out for each of these experiments.

Offline plu

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Re:Rates of Chemical Reaction
« Reply #3 on: January 28, 2006, 10:26:37 AM »
Great!  Now, you can make a rate vs. concentration graph (rate = change in concentration/time).  From that, you can deduce the initial rate of the three experimental reactions and thus the order of the reaction in respects to the three reagents.

Offline Donaldson Tan

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Re:Rates of Chemical Reaction
« Reply #4 on: January 29, 2006, 04:12:10 AM »
Quick Question:
The formula for rate = k (reactant)^a [reactant]^b [reactant]^c

what are the 3 reactants in the  rate equation?

I am not sure if you have sufficient data. there are 4 unknowns (a,b,c,k) and therefore you need 4 sets of experimental data to solve for each unknown.
"Say you're in a [chemical] plant and there's a snake on the floor. What are you going to do? Call a consultant? Get a meeting together to talk about which color is the snake? Employees should do one thing: walk over there and you step on the friggin� snake." - Jean-Pierre Garnier, CEO of Glaxosmithkline, June 2006

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