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Chemistry Forums for Students => Undergraduate General Chemistry Forum => Topic started by: [V] on November 06, 2010, 01:09:21 AM

Title: 1/4th Life expression for First Order Rxn
Post by: [V] on November 06, 2010, 01:09:21 AM
I must derive the 1/4th life expression for a first order rxn.
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do I set (https://www.chemicalforums.com/proxy.php?request=http%3A%2F%2Fwww.forkosh.dreamhost.com%2Fmimetex.cgi%3F%7B+t%3D1%2F4+%7D&hash=589759d9022839a71f83367db451756f81c603b3) ?
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What am I doing wrong here? The answer is allegedly (https://www.chemicalforums.com/proxy.php?request=http%3A%2F%2Fwww.forkosh.dreamhost.com%2Fmimetex.cgi%3F%7B%5Cfrac%7B1.386%7D%7Bk%7D%7D&hash=af5eabfc3d404277b227196bb05aa815519a484b)

However, this answer key has been wrong before. Can someone please confirm/deny this?

Thank you
Title: Re: 1/4th Life expression for First Order Rxn
Post by: Schrödinger on November 06, 2010, 12:40:28 PM
You were asked to find t1/4. Why did you set t = 1/4?

t1/4 = (ln4)/k.

That would be the final answer