Identifying First and Second Order


Moderators: Chem_Mod, Chem_Admin

Madelyn Romberg 1H
Posts: 102
Joined: Tue Oct 02, 2018 12:16 am

Identifying First and Second Order

Postby Madelyn Romberg 1H » Fri Mar 13, 2020 1:52 pm

How do reaction mechanisms indicate first or second order? Can i get a description on things to look for to identify and connect the two?

Chris Tai 1B
Posts: 102
Joined: Sat Aug 24, 2019 12:16 am

Re: Identifying First and Second Order

Postby Chris Tai 1B » Fri Mar 13, 2020 4:30 pm

One easy way to determine the order of the reaction is to look at the rate law for the reaction. If there is one reactant, then the order of the reaction will be an order of one. If there are two reactants, then the reaction will be of order two. However, it's also important to look at the coefficients of the reactants before creating the rate law. A good rule of thumb is to add up the exponents for each of the reactants in the rate law = k[A]^a[B]^b[C]^c where k is the rate constant. Once you add up a, b, and c, you'll get the order of the reaction

Joowon Seo 3A
Posts: 100
Joined: Sat Aug 24, 2019 12:17 am

Re: Identifying First and Second Order

Postby Joowon Seo 3A » Fri Mar 13, 2020 5:54 pm

If you plot ln of reactant with time and it is a straight line it is first order. If you plot 1/R vs time and it is a straight line it is second order.

jisulee1C
Posts: 149
Joined: Thu Jul 25, 2019 12:17 am

Re: Identifying First and Second Order

Postby jisulee1C » Fri Mar 13, 2020 6:17 pm

you can look at the graphs, look at the units for the rate constant, and also determine using a table of concentrations


Return to “Reaction Mechanisms, Reaction Profiles”

Who is online

Users browsing this forum: No registered users and 3 guests