## Half Life

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

Samantha Pacheco 2K
Posts: 60
Joined: Fri Sep 28, 2018 12:29 am

### Half Life

Will the half life equations be given to us or will we have to derive them?

Chem_Mod
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### Re: Half Life

While the formula sheets vary from year to year, it's likely that if these half-life equations were on the most recent exam, they will be on the final exam formula sheet. :)

kateminden
Posts: 63
Joined: Fri Sep 28, 2018 12:24 am

### Re: Half Life

On the equation sheet on the website, the half-life formulas are given. However, the equation sheet does not specify which order reaction each equation is for, so make sure that you know the difference between the equations.

lukezhang2C
Posts: 59
Joined: Fri Sep 28, 2018 12:18 am

### Re: Half Life

Half life equations are given in the equation sheet, but they will not tell you which half-life equation corresponds to which order of reaction. You can also derive them using the standard half life equation, solving for t when the concentrations are half of the initial.

Sydney Tay 2B
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Joined: Fri Sep 28, 2018 12:20 am

### Re: Half Life

The half life equations are on the equation sheet

Anmol_cheema_2F
Posts: 60
Joined: Fri Sep 28, 2018 12:26 am

### Re: Half Life

The half lives are provided on the formula sheet.

kristi le 2F
Posts: 102
Joined: Thu Jul 11, 2019 12:15 am

### Re: Half Life

They will likely be on the formula sheet, but if you do need to derive the formula, plug in t=1/2 to get the half life formula.

Jessa Maheras 4F
Posts: 121
Joined: Fri Aug 02, 2019 12:16 am

### Re: Half Life

lukezhang2C wrote:Half life equations are given in the equation sheet, but they will not tell you which half-life equation corresponds to which order of reaction. You can also derive them using the standard half life equation, solving for t when the concentrations are half of the initial.