Question about Moles of Solute

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Diana Aguilar 3H
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Question about Moles of Solute

Postby Diana Aguilar 3H » Mon Oct 05, 2020 12:29 pm

When diluting a solution, will the moles of the solute always remain the same or are there certain circumstances that will cause the amount of moles to change?

Leyna Tran 2D
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Re: Question about Moles of Solute

Postby Leyna Tran 2D » Mon Oct 05, 2020 12:32 pm

The key concept we learned is that when diluting a solution, the moles of solute will remain the same. I believe it will always be the same, because when we dilute a solution, we are only adding more solvent, not solute.

SophiaNguyen_2L
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Re: Question about Moles of Solute

Postby SophiaNguyen_2L » Mon Oct 05, 2020 12:33 pm

I believe the moles of the solute will stay the same because typically when you're diluting a solution, you're simply just adding water to change the volume of the solution. Doing so decreases the molarity of a solution.

Saumya Tawakley 1E
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Re: Question about Moles of Solute

Postby Saumya Tawakley 1E » Mon Oct 05, 2020 12:35 pm

During dilution, moles of solute will always remain the same. I would imagine that they would only change if you are adding additional quantities of solute, but in that case it wouldn't be a dilution anymore and the process to solve it would be very different.

JonathanSung_2G
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Re: Question about Moles of Solute

Postby JonathanSung_2G » Mon Oct 05, 2020 12:37 pm

When diluting a solution, it is the concentration (molarity) of the solution that will change. Mathematically, if concentration c=n(moles)/v(volume), diluting the solution will increase the volume v but the moles n will stay the same. The moles of solute will only increase if more solute is added.

Ria Nawathe 1C
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Re: Question about Moles of Solute

Postby Ria Nawathe 1C » Mon Oct 05, 2020 12:37 pm

For dilution, you start with a solution of a certain concentration and just add solvent to decrease the concentration. The only thing that's changing is total volume of the solution, the moles of solute always stays the same.

SelenaDahabreh1D
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Re: Question about Moles of Solute

Postby SelenaDahabreh1D » Mon Oct 05, 2020 12:41 pm

Here's how I like to think of it (and this is a great example provided by Dr. Lavelle in today's lecture):

Imagine you have a vitamin C (C6H8O6) tablet. When you add water to that tablet and that tablet dissolves, have the moles in that tablet changed? The answer to that would be no. Thus, in these instances, you are not merely changing or altering the moles in the vitamin C tablet, you are simply adding water to it. Thus, no, there won't be any circumstances in which the number of moles of solute change in dilution calculations.

VincentLe_3A
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Re: Question about Moles of Solute

Postby VincentLe_3A » Mon Oct 05, 2020 12:44 pm

The moles of the solute will stay the same throughout dilution since we are not adding or removing any amounts of the solute. Dilution only changes the concentration of the solute within a certain volume, not the amount of solute itself.

Jasraj Parmar 3H
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Re: Question about Moles of Solute

Postby Jasraj Parmar 3H » Mon Oct 05, 2020 12:48 pm

The moles of solute will always stay the same. If you add water that will only decrease the concentration of that solution but will not change the moles of solute. If you add the water the volume will increase also. In general, the volume and concentration( Molarity) can change but it is not possible for the moles of solute to change.

Hannah Lechtzin 1K
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Re: Question about Moles of Solute

Postby Hannah Lechtzin 1K » Mon Oct 05, 2020 3:51 pm

When diluting a solution the moles of solute remain the same. For example, if you put a teaspoon of salt into a cup of water and allow it to dissolve, there will still be a teaspoon of salt in the water. If you were to then add another cup of water to your saltwater solution there would still be 1 teaspoon of salt in your saltwater. This works the same way with moles of solute. If you dissolve 5 mol of a solute into water there will still be 5 mol of that solute in the solution, unless you choose to add more solute to the water.

Samuel Flores 1E
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Re: Question about Moles of Solute

Postby Samuel Flores 1E » Mon Oct 05, 2020 3:58 pm

When diluting a solution, the moles of solute will always be the same. By diluting the solution (usually via adding water to that solution), you’re increasing the Volume of the Solution, while the moles Of solute remain the same.
This of course will decrease the molar concentration of the solution (Molarity=moles of solute/Volume of Soln) but moles of solute will always be the same.


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