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Chemistry Forums for Students => High School Chemistry Forum => Topic started by: Shahab Mirza on October 03, 2014, 07:10:09 AM

Title: P + Q → R + S , THE RATE OF REACTION IS INDEPENDENT OF P. but how to solve help?
Post by: Shahab Mirza on October 03, 2014, 07:10:09 AM
This type of question come in our exams usually that.
If the Reaction
P+Q → R + S
is described as being of zero order with respect to P, it means that.
Answer: THE RATE OF REACTION IS INDEPENDENT OF THE CONCENTRATION OF P.

I want to ask that, what is such thing in this reaction that we should write this answer , I mean how to solve it or what , thanks i have MCAT exams please reply
Title: Re: P + Q → R + S , THE RATE OF REACTION IS INDEPENDENT OF P. but how to solve help?
Post by: mjc123 on October 03, 2014, 11:57:56 AM
The order of a reaction with respect to P is the power to which the concentration of P is raised in the rate equation. For example, if the rate is proportional to [P]2, we say it is second order in P.
To say that the reaction is zero order in P means that the rate is proportional to [P]0. Now as [P]0 = 1 for all values of [P], that means that the rate of reaction is independent of [P].
Title: Re: P + Q → R + S , THE RATE OF REACTION IS INDEPENDENT OF P. but how to solve help?
Post by: Shahab Mirza on October 03, 2014, 05:11:57 PM
Quote from: mjc123 on October 03, 2014, 11:57:56 AM
The order of a reaction with respect to P is the power to which the concentration of P is raised in the rate equation. For example, if the rate is proportional to [P]2, we say it is second order in P.
To say that the reaction is zero order in P means that the rate is proportional to [P]0. Now as [P]0 = 1 for all values of [P], that means that the rate of reaction is independent of [P].

oh so it is the case, then wouldnt be it more better to say that
zero order reactions are independent of concentrations?
Title: Re: P + Q → R + S , THE RATE OF REACTION IS INDEPENDENT OF P.
Post by: mjc123 on October 04, 2014, 02:35:40 PM
Better than what? Isn't that what you said in the first place?
Title: Re: P + Q → R + S , THE RATE OF REACTION IS INDEPENDENT OF P. but how to solve help?
Post by: Shahab Mirza on October 04, 2014, 03:05:54 PM
sir , at first place i said this, Answer: THE RATE OF REACTION IS INDEPENDENT OF THE CONCENTRATION OF P.

but i didnt knew how that answer came i just copied answer from back of my chemistry text book, but when I read it in detail i came to knew that zero order reaction is independent of concentration. now then i knew that what this question really wanted to ask.