## Quiz 2 prep #3

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

Jose_Arambulo_2I
Posts: 35
Joined: Wed Sep 21, 2016 2:59 pm

### Quiz 2 prep #3

This question gives the reaction N2O---> N2 + O2 and it gives the rate constant r*k[N2O]. Would this be first order because of the given rate law, or do we have to balance it then add an exponent (in this case 2) to the concentration?

Maria_Contreras_3A
Posts: 13
Joined: Fri Jul 15, 2016 3:00 am
Been upvoted: 1 time

### Re: Quiz 2 prep #3

I would assume that you are given the fact that it is a first order reaction since it states "rate=k[N2O]"

Beata_Vayngortin_3L
Posts: 21
Joined: Fri Jul 22, 2016 3:00 am
Been upvoted: 1 time

### Re: Quiz 2 prep #3

The rate constant helps you determine the order of the reaction. You cannot just assume what the order of the reaction will be based on its balanced form and by looking at the stoichiometric coefficients.

Maria_Contreras_3A
Posts: 13
Joined: Fri Jul 15, 2016 3:00 am
Been upvoted: 1 time

### Re: Quiz 2 prep #3

So how would the rate constant in this case help us determine the order of the reaction? I understand that through experiments you can compare the rate constants and their initial concentration to conclude the order reaction, right?

Melanie Martinez 1K
Posts: 10
Joined: Wed Sep 21, 2016 2:55 pm

### Re: Quiz 2 prep #3

Can you explain exactly how to determine the order of the reaction? Im still not sure how the rate constant would help.