Heres the differential rate equation for a 0 order reaction in chemistry:(adsbygoogle = window.adsbygoogle || []).push({});

[itex]Rate = {{-d[A]} / {dt}} = k[/itex]

which can be rearranged to this:

[itex]-d[A] = dt k[/itex]

and when you integrate this you get the integrated rate equation but I don't understand how this works. The site I'm reading says you integrate both sides of the equation and get this:

http://www.uni-regensburg.de/Fakultaeten/nat_Fak_IV/Organische_Chemie/Didaktik/Keusch/Grafik/ord_z5.gif

is that supposed to be a definite integral or something? Anyhow, after integrating they get this:

http://www.uni-regensburg.de/Fakultaeten/nat_Fak_IV/Organische_Chemie/Didaktik/Keusch/Grafik/ord_z3.gif

I don't get it. Firstly [A] and t are variables so shouldn't they be raised a power and get divided by 2? In other words, shouldn't they become [itex][A]^{2} / 2[/itex] and [itex]t^{2} / 2[/itex]? Secondly, whats going on with the d. d means the change in something but I've never seen it been integrated before so I don't know what happens to it. Why did it disappear?

The 1st order equation has me equally confused:

http://www.uni-regensburg.de/Fakultaeten/nat_Fak_IV/Organische_Chemie/Didaktik/Keusch/Grafik/ord1_ip1.gif

integratin that, they get this:

http://www.uni-regensburg.de/Fakultaeten/nat_Fak_IV/Organische_Chemie/Didaktik/Keusch/Grafik/ord1-3.gif

has does d[A]/[A] become ln[A]?

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# Integrating the differential rate equation

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