G7 Clarification

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Adam_Ventura_1H
Posts: 104
Joined: Wed Sep 30, 2020 10:05 pm

G7 Clarification

Postby Adam_Ventura_1H » Mon Oct 05, 2020 7:19 pm

I have been reading the question and I am not quite sure what exactly it is asking me. I was hoping someone could clarify a bit, it does not seem too difficult but maybe the way the question is asked does not resonate with me. Does the solution weigh 510g or is that how much solute should be in it?

Question: You need to prepare 510. g of an aqueous solution containing 5.45% KNO3 by mass. Describe how you would prepare the solution and what mass of each component you would use.

Samantha Pedersen 2K
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Re: G7 Clarification

Postby Samantha Pedersen 2K » Mon Oct 05, 2020 7:27 pm

The entire solution weighs 510. g, and only 5.45% of that is the solute (or KNO3). You can use that fact to determine how many grams of KNO3 you'll need, then you can subtract the number of grams of KNO3 from the total mass of the solution to determine how many grams of water you'll need. I hope that helps!

Saumya Tawakley 1E
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Joined: Wed Sep 30, 2020 9:59 pm

Re: G7 Clarification

Postby Saumya Tawakley 1E » Mon Oct 05, 2020 7:28 pm

I believe that the total mass of the solution (solute + solvent) should be 510g. So you would find the mass of solute needed by finding 5.45% of 510, and that would be the mass of KNO3 needed. You would then subtract that number from 510g to find the mass of water needed for the solution.
In terms of preparing the solution, you would just state that you need to mix (0.0545*510)g of KNO3 and [510-(0.0545*510)]g of water.
Hope that helped!

Melis Kasaba 2B
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Joined: Wed Sep 30, 2020 9:49 pm

Re: G7 Clarification

Postby Melis Kasaba 2B » Mon Oct 05, 2020 7:30 pm

I believe 510. g is how much the aqueous solution with the solute (KNO3) weighs. So you need to calculate how many grams of KNO3 are in the solution and then how many grams of water (since it's an aqueous solution water is the other component). The solution would then be prepared by pouring the calculated mass of H2O into a beaker and weighing the calculated mass of KNO3 and then mixing it into the beaker until it completely dissolves.

Adam_Ventura_1H
Posts: 104
Joined: Wed Sep 30, 2020 10:05 pm

Re: G7 Clarification

Postby Adam_Ventura_1H » Mon Oct 05, 2020 7:57 pm

Thank you for the help. I now understand that the exercise is easy, I just was not understanding the question correctly. All cleared up now.


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