How to tell difference btwn thermo and kinetics  [ENDORSED]

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Nicole Jacobs 1C
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How to tell difference btwn thermo and kinetics

Postby Nicole Jacobs 1C » Fri Mar 02, 2018 5:33 pm

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

Gurvardaan Bal1L
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Re: How to tell difference btwn thermo and kinetics

Postby Gurvardaan Bal1L » Fri Mar 02, 2018 5:47 pm

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
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Re: How to tell difference btwn thermo and kinetics

Postby vicenteruelos3 » Fri Mar 02, 2018 10:44 pm

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
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Re: How to tell difference btwn thermo and kinetics

Postby Angela G 2K » Sat Mar 03, 2018 12:50 am

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
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Re: How to tell difference btwn thermo and kinetics

Postby Masih Tazhibi 2I » Sat Mar 03, 2018 1:21 pm

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
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Re: How to tell difference btwn thermo and kinetics

Postby zanekoch1A » Sat Mar 03, 2018 3:28 pm

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

Postby Chem_Mod » Mon Mar 05, 2018 1:58 pm

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
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Re: How to tell difference btwn thermo and kinetics

Postby Kayla Ikemiya 1E » Mon Mar 05, 2018 7:05 pm

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


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