## How to tell difference btwn thermo and kinetics [ENDORSED]

Nicole Jacobs 1C
Posts: 59
Joined: Thu Jul 13, 2017 3:00 am

### How to tell difference btwn thermo and kinetics

How do you tell if the reaction is controlled by thermodynamics? by kinetics?

Gurvardaan Bal1L
Posts: 54
Joined: Fri Sep 29, 2017 7:04 am
Been upvoted: 2 times

### Re: How to tell difference btwn thermo and kinetics

Nicole Jacobs 1C wrote:How do you tell if the reaction is controlled by thermodynamics? by kinetics?

Kinetics is the rate/speed of the reaction, while thermodynamics is how favorable the reaction is to occur.

vicenteruelos3
Posts: 42
Joined: Fri Sep 29, 2017 7:07 am

### Re: How to tell difference btwn thermo and kinetics

all reactions have to overcome a specific activation energy this is what determines the rate of the reaction (kinetics)
whether or not the products are in a higher or lower energy state than the reactants determines if the reaction is favorable (thermodynamics)

Angela G 2K
Posts: 30
Joined: Fri Sep 29, 2017 7:06 am

### Re: How to tell difference btwn thermo and kinetics

Thermodynamics predicts the spontaneity, while kinetics predicts the rate/speed of the reaction. If a reaction is spontaneous (thermodynamically unstable) but the reaction doesn't occur at a measurable rate, then it is controlled by kinetics (kinetically stable). For example, C(diamond) spontaneously turns into C(graphite), but we don't see this reaction occur because it has a very high activation energy and occurs very slowly (kinetics is controlling this reaction).

Masih Tazhibi 2I
Posts: 33
Joined: Fri Sep 29, 2017 7:06 am

### Re: How to tell difference btwn thermo and kinetics

Another key point is that thermodynamics really buckled down on the initial and final states of a system, dealing mostly with state functions and just looking at relative changes in work, energy, and entropy.

What seems to be the most different about kinetics is that it focuses on the very path portion of the reaction which thermodynamics ignored. It allows us to have another layer of understanding about how a reaction proceeds, to not just look at the initial and final states, but to also have some information regarding HOW the reaction proceeded, and what the potential barriers were.

zanekoch1A
Posts: 25
Joined: Thu Jul 13, 2017 3:00 am

### Re: How to tell difference btwn thermo and kinetics

All reactions are affected by both but some are more dependent on one or the other. Kinetics and thermodynamics are two ways or describing the same phenomenon; its like saying I have to drive for 100 miles or I have to drive for 2 hours. Both are measuring the same thing in different ways.

Chem_Mod
Posts: 18892
Joined: Thu Aug 04, 2011 1:53 pm
Has upvoted: 716 times

### Re: How to tell difference btwn thermo and kinetics  [ENDORSED]

As previously said, all reactions are governed by kinetics and thermodynamics. They are not the same thing however. Thermodynamics refers to the change in energy between the initial and final state, and the thermodynamic product of a reaction would be the most sable product. Kinetics describes specifically rates. Sometimes the kinetic product, which is the fastest one generated, is not actually the most stable product. It just has the lowest energy barrier, so it can be formed faster. What reactions are governed more by which factor is highly reaction-dependent.

Kayla Ikemiya 1E
Posts: 56
Joined: Fri Sep 29, 2017 7:04 am

### Re: How to tell difference btwn thermo and kinetics

Can you please provide an example problem where we would have to apply this concept?

### Who is online

Users browsing this forum: No registered users and 2 guests