C in ICE Box

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Ashley Lopez 3J
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Joined: Wed Sep 30, 2020 10:06 pm

C in ICE Box

Postby Ashley Lopez 3J » Sun Jan 17, 2021 10:48 pm

How do we know when the Change in equilibrium is negative or positive for products/reactants?

Joyce Pang 2H
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Joined: Wed Sep 30, 2020 9:59 pm

Re: C in ICE Box

Postby Joyce Pang 2H » Sun Jan 17, 2021 10:53 pm

When something reacts to form product, the reactant's change would be negative, because you're "losing" the reactant in favor of forming more product. So naturally, the change in product would be positive, since you're gaining some.

Xinyu Li 1C
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Re: C in ICE Box

Postby Xinyu Li 1C » Sun Jan 17, 2021 10:55 pm

The change in reactants is always negative and the change in products is always positive because reactants are being used up to form products.

Sable Summerfield
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Re: C in ICE Box

Postby Sable Summerfield » Sun Jan 17, 2021 10:56 pm

So, what exactly does the x mean? Is it like a placeholder for the value of the concentration?

Gustavo_Chavez_1K
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Re: C in ICE Box

Postby Gustavo_Chavez_1K » Sun Jan 17, 2021 10:57 pm

Yeah, when you are losing reactant then the reactant's change would be negative and with that the product's change would be positive since you are gaining some. This could also be done in the reverse order so gaining reactant and losing product.

Michael Cardenas 3B
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Re: C in ICE Box

Postby Michael Cardenas 3B » Sun Jan 17, 2021 10:57 pm

The change in reactants is usually negative and the change in the products is usually positive because naturally the reactants should decrease, while the products increase in concentration.

Mina Tadros 3L
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Re: C in ICE Box

Postby Mina Tadros 3L » Sun Jan 17, 2021 10:58 pm

Whatever is reacting to form something else will be the negative one. That is because as the reaction proceeds, the reactant's concentration will begin to decrease while the product(s) it is forming will be increasing. That is why it would be positive for products, and for reactants, it would be negative.

Abraham De Luna
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Re: C in ICE Box

Postby Abraham De Luna » Sun Jan 17, 2021 10:59 pm

The change in reactants is always negative while the change in products is always positive.

Sofia Azmat 1I
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Re: C in ICE Box

Postby Sofia Azmat 1I » Sun Jan 17, 2021 11:01 pm

This depends on what you have initially, and what you will end up losing in the reaction. If you are using up more reactant to form the product, you would use a negative sign for the reactants and positive for the products. If the reaction is reversible, look at the arrow between the balanced equation, and whatever it points to increases, and whatever it points away from decreases.

Ariana Flores 3F
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Re: C in ICE Box

Postby Ariana Flores 3F » Sun Jan 17, 2021 11:01 pm

so you couldn't have a positive reactant and positive product value, one needs to be negative?

Joyce Pang 2H
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Joined: Wed Sep 30, 2020 9:59 pm

Re: C in ICE Box

Postby Joyce Pang 2H » Sun Jan 17, 2021 11:03 pm

Sable Summerfield wrote:So, what exactly does the x mean? Is it like a placeholder for the value of the concentration?


Yea, it would represent the change in concentration. Like x amount reacted to form product, and is thus subtracted from the initial concentration.

Carolina Gomez 2G
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Re: C in ICE Box

Postby Carolina Gomez 2G » Sun Jan 17, 2021 11:05 pm

The change in equilibrium is negative/ positive depending on the direction of the reaction. If the reaction is going towards the products then the reactants will be negative and the products will be positive. This means that there is excess reactants that will form more products until it reaches equilibrium, hence why the products is positive. If the reaction is going towards the reactants, the products are negative and the reactants are positive. This means that products are going to form reactants until the reaction is in equilibrium.

Sofia Azmat 1I
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Joined: Fri Aug 30, 2019 12:16 am

Re: C in ICE Box

Postby Sofia Azmat 1I » Wed Jan 20, 2021 7:43 pm

Ariana Flores 3F wrote:so you couldn't have a positive reactant and positive product value, one needs to be negative?

As far as I know, yes. One will always be positive and the other will always be negative. To determine which is which, you need to look at what the initial values are as well as what is being lost and what is being gained in the reaction.

VincentLe_3A
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Re: C in ICE Box

Postby VincentLe_3A » Wed Jan 20, 2021 11:28 pm

In the specific direction that the reaction takes place, the reactants would have negative change because they are being used up while the products would have a positive change because they are being formed. The coefficients for these changes can be found in corresponding stoichiometric coefficients the balanced chemical equation for the reaction.

Kiyoka Kim 3C
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Re: C in ICE Box

Postby Kiyoka Kim 3C » Thu Jan 21, 2021 4:37 am

If you were given the initial concentrations for the reactants and products, you could calculate Q to check which direction the reaction will proceed. Then from there whatever is the "reactant" will have a negative change, and the "product" will have a positive change.

Olivia Smith 2E
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Re: C in ICE Box

Postby Olivia Smith 2E » Thu Jan 21, 2021 8:50 am

It will be negative anytime those molecules are being transformed into another molecule. Such as a reactant to product scenario. It simply means you are taking some of one reactant or sometimes product if given the product values, to form the product or reactant!

Lucy_Balish_3G
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Re: C in ICE Box

Postby Lucy_Balish_3G » Thu Jan 21, 2021 10:09 am

The change for products is negative because they are going to form reactants. Because reactants are being formed, their C is positive.

Kathy_Li_1H
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Re: C in ICE Box

Postby Kathy_Li_1H » Thu Jan 21, 2021 12:59 pm

Hi! I believe it just depends on the equation. If you have more of the reactant than product, the forward reaction would likely take place and as a result, the second row would be negative for the reactants and positive for the reactant. This same principle applies in reverse reactions or when there is more product than reactant.

Chloe Shamtob 2H
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Re: C in ICE Box

Postby Chloe Shamtob 2H » Thu Jan 21, 2021 1:32 pm

To know whether a change in equilibrium is negative or positive for the reactants, you must pay attention to the direction of the reactions. When a reaction favors the products (reactants form from product), the reactant's change (or C in the ice box) would be negative. When a reaction favors the reactants (products form from reactants) the change in product would be positive. This is because you are gaining product and loosing reactant.

Sheryl Ocampo 1D
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Re: C in ICE Box

Postby Sheryl Ocampo 1D » Thu Jan 21, 2021 2:18 pm

the amount in the products is going to decrease, which will cause the products to increase


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