I am trying to calculate the mass of NaCl(aq) in an unknown solution. The setup

Question

I am trying to calculate the mass of NaCl(aq) in an unknown solution. The setup is that I have a buret of a solution of AgCl(s) in water being added to 100mL of unknown amount of NaCl(aq). The assignment wants me to first calculate the molarity of Ag+  ions in a solution made from 0.001906g AgCl(s) and 1000mL water. I calculated that as 1.330x10-5 mol/L Ag+ ion concentration. I am supposed to use the Ksp and the [Ag+] to solve for [Cl-] given the following equation:

[Cl-NaCl(aq)] = Ksp / [Ag+] where Ksp is given to me as 1.830x10-10

Now, when I plug the numbers in and solve for [Cl-NaCl(aq)], I get 1.376x10-5 mol/L Cl- and I'm told that [Cl-] and [NaCl(aq)] are in a 1:1 ratio so they will equal each other in my quest to determine the mass of NaCl in the unknown solution. So, I am taking 1.376x10-5 mol/L NaCl(aq) and trying to find the mass from this number. Here's where I seem to be running into some trouble. This number is how many moles are in 1 liter, but my starting solution was 100mL. So, I have tried to calculate how many moles are in 100mL. Then, I am using NaCl's molar mass (58.4428 grams per mole).

(1.376x10-5 mol NaCl / 1000mL) * 100mL = 1.376x10-6 moles NaCl in 100mL of solution

(1.376x10-6 moles NaCl / 1 mol NaCl) * MM NaCl (58.4428g) = 8.04x10-5 g NaCl in unknown solution

I only get one more chance to answer, so I would appreciate any feedback on this. Thank you in advance!

Explanation / Answer

Yes. The calculation you have done correct. And mass of NaCl present in 100 mL solution is 8.04*10^-5 g.

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