Integrating the first order rate law

In summary, the first order rate law is a mathematical expression that describes the rate at which a chemical reaction occurs. It can be integrated using the integrated rate law to solve for the concentration of the reactant at any given time. The half-life of a first order reaction is the time it takes for the concentration of the reactant to decrease by half, and it is affected by factors such as temperature, concentration, and the presence of catalysts. The first order rate law has many real-world applications in areas such as pharmacology, environmental science, and chemical engineering.
  • #1
kasse
384
1
-d[A]/dt = k[A]

- Int( d[A]/[A]) = Int (k dt)

- ( ln[A] + ln[A0] ) = kt

ln[A] = -kt - ln[A0]


Where am I wrong?
 
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  • #2
- ( ln[A] - ln[A0] ) = kt
 
  • #3
Why "-"?
 
  • #4
It's always final - initial when doing integrals i.e.

[tex]F(b) - F(a) = \int_{a}^{b} f(x) dx[/tex]

and not +.
 

FAQ: Integrating the first order rate law

What is the first order rate law?

The first order rate law is a mathematical expression that describes the rate at which a chemical reaction occurs. It is written in the form of d[A]/dt = -k[A], where [A] is the concentration of the reactant, t is time, and k is the rate constant.

How do you integrate the first order rate law?

To integrate the first order rate law, you can use the integrated rate law, which is ln[A] = -kt + ln[A]0. This equation allows you to solve for the concentration of the reactant at any given time, t, by plugging in the initial concentration, [A]0, and the rate constant, k.

What is the half-life of a first order reaction?

The half-life of a first order reaction is the amount of time it takes for the concentration of the reactant to decrease by half. It is calculated using the equation t1/2 = ln2/k, where k is the rate constant.

What factors can affect the rate constant in a first order reaction?

The rate constant in a first order reaction can be affected by factors such as temperature, concentration of reactants, and the presence of catalysts. Generally, an increase in temperature or concentration will result in a higher rate constant, while the presence of a catalyst can lower the rate constant.

How is the first order rate law used in real-world applications?

The first order rate law is used in many areas of science and technology, including pharmacology, environmental science, and chemical engineering. It is used to model the rate of drug metabolism, the decay of radioactive materials, and the degradation of pollutants in the environment, among other applications.

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