Page 1 of 1

what if

Posted: Mon Mar 11, 2019 7:21 pm
by inlovewithchemistry
what would the overall rate for the reaction H2 + I2 --> 2HI look like if it was first order?

i know that the second order formula is rate = k[H2][I2], but dont know what to give if it asked for first order.

Re: what if

Posted: Mon Mar 11, 2019 7:27 pm
by Mahir_Hasan2C
It will still be second order since each reactant is first order.

Re: what if

Posted: Mon Mar 11, 2019 11:02 pm
by Chem_Mod
For each given reaction, there would be only one unique rate law. Thus, the rate law of a reaction cannot sometimes be first order, sometimes second order. In addition, you cannot determine directly from the written reaction what order it is. It can only be determined by experiment.

Re: what if

Posted: Mon Mar 11, 2019 11:21 pm
by Charles Hood Disc 1C
You can't just make it first order. The order of a reaction is determined empirically and cannot be changed. However, if you had a reaction that was simply first order the rate law would appear as Rate = k[A]. Also, a second order rate law is rate = k[A]2.