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Half life
Posted: Fri Mar 15, 2019 1:55 am
by Dakota_Campbell_1C
Where does the 0.693 come from in the half life equation for first order reactions. Will that value ever change? I just want to know where it comes from and why we use it.
Re: Half life
Posted: Fri Mar 15, 2019 2:08 am
by Samantha Silva 1F
It is the natural logarithm of 2.
Re: Half life
Posted: Fri Mar 15, 2019 3:08 am
by Brandon Mo 4K
Using the integrated rate law of the first order reactions: ln [A] = -k t + ln [A]o, you can solve for the half-life (t1/2) by setting [A]= (1/2)[A]o.
Eventually you get, t1/2 = ln(2)/k or 0.693/k.
Re: Half life
Posted: Fri Mar 15, 2019 4:13 am
by MadisonB
After deriving the equation you are left with ln(2)/k.
Re: Half life
Posted: Fri Mar 15, 2019 12:01 pm
by Ricky Ma DIS 4E
What are the different kinds of answers that the half life equation can give us?