## Equation in the Book vs. in Lecture

$\frac{d[R]}{dt}=-k[R]; \ln [R]=-kt + \ln [R]_{0}; t_{\frac{1}{2}}=\frac{0.693}{k}$

Lily Guo 1D
Posts: 64
Joined: Fri Sep 29, 2017 7:03 am

### Equation in the Book vs. in Lecture

The equation that the book gives for the integrated rate law of first-order reactions is [A]t = [A]0e-kt, but the equation for the integrated rate law of first-order reactions given in lecture is ln[A] = -kt + ln[A]0. Does it matter which equation we use since both are essentially the same? Is one better or easier to use than the other?

Hubert Tang-1H
Posts: 44
Joined: Thu Jul 27, 2017 3:00 am

### Re: Equation in the Book vs. in Lecture

Since we can derive one equation from the other, there doesn't seem to be any impact if we use one or the other. It just depends on which one you feel more comfortable using.

Janet Nguyen 2H
Posts: 51
Joined: Fri Sep 29, 2017 7:05 am

### Re: Equation in the Book vs. in Lecture

They include both in the book. It just depends on the problem and what you are solving for. Like, if you are solving for time t or k, the equation with ln would be better. If you are solving for concentration, the exponential form would be easier to use