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

Amy Lefley 1J
Posts: 60
Joined: Fri Sep 28, 2018 12:15 am

How do we know that radioactive decay is a first order reaction?

josie 1C
Posts: 18
Joined: Fri Sep 28, 2018 12:19 am

### Re: Radioactive Decay

because the rate of decay is directly proportional to the concentration of atoms

Ray Guo 4C
Posts: 90
Joined: Fri Sep 28, 2018 12:15 am

### Re: Radioactive Decay

Because it has a constant half-life. All first-order reactions have constant half-lives.

Patrick Cai 1L
Posts: 93
Joined: Fri Sep 28, 2018 12:25 am

### Re: Radioactive Decay

It was through experimental verification that we were able to tell over a given period of time, now called a radioactive substance's half life, that half of the substance would decay away; this fits within our model of a first order process.