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Chemistry Forums for Students => Undergraduate General Chemistry Forum => Topic started by: moun7 on October 29, 2014, 06:06:09 PM

Title: Quick question about rate laws/kinetics.
Post by: moun7 on October 29, 2014, 06:06:09 PM
Hello,

Say I have a reaction given by,

X + Y  :rarrow: 2Z, k=whatever

and I was asked to determine the rate of production of Z, what effect on the rate does the 2 coefficient have? For example, would the rate be,

rate = k[X][Y], as in if there were no coefficient,

or

rate = (1/2)k[X][Y]

or

rate = 2k[X][Y]

or something entirely different?

Thanks.

Edit: It's a second order reaction.
Title: Re: Quick question about rate laws/kinetics.
Post by: Babcock_Hall on October 29, 2014, 06:11:39 PM
"rate of production of C"  Do you mean C or Z?
Title: Re: Quick question about rate laws/kinetics.
Post by: moun7 on October 29, 2014, 06:13:06 PM
Oops, I meant Z. I had it as A, B, and C, but turns out square brackets around B made parts of the post bold, so I changed it to X, Y, and Z. Also, it's a second order reaction.
Title: Re: Quick question about rate laws/kinetics.
Post by: Irlanur on October 30, 2014, 03:40:21 PM
you can define it however you want, just be aware that k will be different in different definitions. its customary to define the rate of a reaction as the rate of change of the concentration of a species divided by its stochiometric coefficient