1st order equation
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1st order equation
Hi! I am a little confused, when we are solving for first order problems, will we actually ever use the equation ln[A]=-kt+ln[A] or do you just use rate=k[A]?
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Re: 1st order equation
We use the equation rate=K[A] when we are solving for the rate or the value of K or [A].
We use the equation ln[A]= ln[A]initial -kt when we are solving for variables like time which are not represented in the first equation. This equation is called the integrated rate law as it allows us to calculate the concentrations of reactants or products any time after the start of the reaction.
We use the equation ln[A]= ln[A]initial -kt when we are solving for variables like time which are not represented in the first equation. This equation is called the integrated rate law as it allows us to calculate the concentrations of reactants or products any time after the start of the reaction.
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Re: 1st order equation
It depends on the equation as the integrated rate of k[A] is ln[A]=-kt+ln[A], which we use to find {A} at a given time.
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Re: 1st order equation
It depends on the values they provide for you. The integrated rate law is derived from the experimentally determined differential rate law but the only difference is based on a function of concentration and the other one is based on a function of time.
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Re: 1st order equation
Normally we use the equation with ln[A] when we are trying to find the concentration of a species given time. That is the integrated rate law and can also be used to find the half life of particular species in a reaction. Rate = k[A] is used when just trying to find the overall rate of the reaction when given the initial concentration and K. I hope this helps!
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Re: 1st order equation
I think the only time we really use the integrated rate law, ln[A]=-kt+ln[A], is if we are given a problem that asks us to find the concentration at a certain time. Time is the main thing we solve with that equation.
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Re: 1st order equation
The integrated rate law is used when finding concentration at a some time during the course of the reaction. The equation is linear and arranged in y=mx+b format so that we can find concentration with respect to time.
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Re: 1st order equation
Depending on the problem and whats given, you would use ln[A]=-kt+ln[A] if you have to find A or k at a given time. If you are just given K and a concentration, and just need to find the rate of the reaction, you can use rate = k[A].
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Re: 1st order equation
It depends on the problems. you can use ln[A]=-kt+ln[A] in specific instances, such as finding A or k.
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