## First Order Reactions

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

AlyssaBei_1F
Posts: 99
Joined: Fri Sep 28, 2018 12:17 am

### First Order Reactions

In first order reactions, will it always be a straight line like the graph in lecture from today?

Reva Kakaria 1J
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Joined: Fri Sep 28, 2018 12:23 am
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### Re: First Order Reactions

Yes, I believe first order reaction graphs will always be straight lines when they are graphed as ln[R] vs time.

melodyzaki2E
Posts: 61
Joined: Fri Sep 28, 2018 12:18 am

### Re: First Order Reactions

I think the derived ln formula for first order will always be a straight line but I don't think the actual rate law for first order reactions are first order, i'm not totally sure though.

LedaKnowles2E
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### Re: First Order Reactions

In the slides it says a straight line plot of ln[R] vs time means the reaction is 1st-order.

katie_sutton1B
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### Re: First Order Reactions

Yes, It will be a straight line. But I think Lavelle also said if you also see an exponential decrease, that would be [A] graphed and indicate a first order reaction as well

JT Wechsler 2B
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### Re: First Order Reactions

First order reaction graphs are only straight lines when the graph is time vs. ln[A]

Tatum Keichline 2B
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Joined: Fri Sep 28, 2018 12:26 am

### Re: First Order Reactions

I believe it should be a straight line with decreasing slope