Approximations for ICE

705170809
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Approximations for ICE

When can we use approximations like making (x-0.89) become just x?

Arshiya
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Re: Approximations for ICE

In regards to equilibrium equations, you must see the K value when making an assumption. If the K value is less than 10^-3, then you can proceed using x. However, make sure you check your assumption with the 5% condition.

Cole Doolittle 2K
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Re: Approximations for ICE

You can use approximations if the Ka value is less than 1x10^-3. You should check to see that it was appropriate to use approximation by seeing if the equilibrium concentration is less than 5% of the initial concentration.

Jonathan Pai 2I
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Re: Approximations for ICE

When the k value is small, 10^-3 , because so little of the reactants go to products it is negligable.

chris_tsai_4H
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Re: Approximations for ICE

If the value of K is less than 10^-3, then we can assume that the value is too small to have any impact and therefore we can assume that X minus any number becomes just x.

isarose0
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Re: Approximations for ICE

When k is less than 10^-3

Isabelle Fontanilla 1I
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Re: Approximations for ICE

Given the K value, if K<<10^-3, then you may make the approximation. If K is not given, then make the approximation, but be sure to check if the value of x that you found is, indeed, less than 5% of the initial value(s)(concentration/partial pressure)of the components in the system. If x<5% of the initial value(s), then your approximation is valid. If you don't want to waste time verifying, you can always use the quadratic formula to solve for x without approximations(if you don't mind additional work, which might be less productive than the other method).

Also, if the initial value is 0, then the change, no matter how small, is significant, so no approximations should be made.

RachelCheung1A
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Re: Approximations for ICE

when the K is less than 1x10-3, so if the K ends with 10^-4 or smaller. Ex 1.9x10^4 approximate but 1.9x10^-3 don't approximate

Diana Sandoval 1K
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Re: Approximations for ICE

When K is less than 10^-3

allisoncarr1i
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Re: Approximations for ICE

The approximation can only be used if K is very small.

Anjali 4A
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Re: Approximations for ICE

Like everyone said, we make the approximation when K is small - less than 10^-3.

405021651
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Re: Approximations for ICE

when K is less than 10^3

Tony Ong 3K
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Re: Approximations for ICE

as a means to check if your approximations are correct,
remember the 5% rule at the end!

Anna O 2C
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Re: Approximations for ICE

To add on, make sure to always verify at the end that your approximation was less than 5% otherwise the approximation won't hold and you need to use the formula for finding roots.

Tony Chung 2I
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Re: Approximations for ICE

You can do this when your equilibrium constant value is less than 10^-3 because this value is extremely small.

Luis_Yepez_1F
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Re: Approximations for ICE

When K is less than 10^-3, you can just approximate. Always remember to prove the approximation using the 5% rule.

Pritish Patil 1K
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Re: Approximations for ICE

When the k value is less than 10^-3

Aiden Atoori 1C
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Re: Approximations for ICE

I think when k is less than 10^-3

Jack DeLeon 1B
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Re: Approximations for ICE

when k is less than 10^-3, then we can assume that x is small enough to not have an effect in the math

Aleeque Marselian 1A
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Re: Approximations for ICE

If the value of K is less than 10^-3 then the assumption can be made that x is very small and would be negligible.

jocelyntzeng
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Re: Approximations for ICE

K has to be very small so you can assume that x is very small