So anytime I've seen textbooks explain integrated rate laws, they usually start with a reaction of the form A -> B and then from there say, if we know the reaction is first order with respect to [A] then:(adsbygoogle = window.adsbygoogle || []).push({});

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

And then subsequently integrate this to find ln[A]/[A]i = -kt

I get that. My issue is this. From what I always thought, the integrated rate laws are universal, and now that I have this equation I can use it any time I know that a reaction is first order with respect to A. But what if I have an equation of the form:

aA -> B

where there is a stoichiometric coefficient in front of A. If experimental data still tells us that the rate law is first order with respect to A, can I just use the same integrated rate law that I found above? or would I have to say the following:

v = - (1/a) d[A]/dt = k[A]

in which case you would get:

ln[A]/[A]i = -(a)kt

So for a reaction 2A -> B

You would find ln[A]/[A]i = -2kt

Assuming the rate was always first order with respect to [A], wouldn't you get a different integrated rate law for every instance that you have a different stoichiometric factor (a) in front of your reactant? If so why isn't the general form of the equation given as ln[A]/[A]i = -akt

Hope this makes sense - not sure where my reasoning is off

**Physics Forums - The Fusion of Science and Community**

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Does integrated rate law have stoichiometric coefficient?

Loading...

Similar Threads - Does integrated rate | Date |
---|---|

Does this formula exist? (ν' = En/hc) | Jan 1, 2018 |

Does this bond formation release energy? | Dec 29, 2017 |

How does Ethyl isopropyl ketone affect graphene sheets? | Dec 20, 2017 |

Why does liquid argon stop boiling after a while in dewar? | Dec 10, 2017 |

**Physics Forums - The Fusion of Science and Community**