Chemical Forums
Chemistry Forums for Students => Undergraduate General Chemistry Forum => Topic started by: Jackmcnulty on November 11, 2021, 04:04:13 PM
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Consider: A + 2B :rarrow: C + 2D
It is asking me what the order of reaction with respect to B and A are. I understand the rate law that states
Rate = k[A]mBn
However I do not understand where the values for m and n are coming from.
We were also given tabulated data about [A]0, and B0 and Initial Δ[C]/Δt.
Is there something about this tabulated data that should tell me? Where B is not in brackets, the formatting messed it up and it is in fact the molarity of the reactant B.
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Rate = k[A]mBn
However I do not understand where the values for m and n are coming from.
Values "m" and "n" need to be calculated. If you have the data about concentration of A and B I suggest to draw a graph - concentration of A, B, C and D versus time of the reaction.
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However I do not understand where the values for m and n are coming from.
Technically they reflect stoichiometry of the reaction as it happens - which sometimes, in the case of very simple reactions, is eactly what the reaction equation says, but in most cases they reflect so called elementary reactions - which are simpler steps towards the full, complete process, described by the balanced equation.
From the data you have you shoudl be probably able to determine m and n. It is often not trivial to do so, see Rate equation page in wikipedia.
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B in brackets is the format code for bold type. For concentration of B, you can just include a space, e.g. [B ].