Answer: The percent by volume of isopropyl alcohol in a solution made by mixing 120 mL of the alcohol with enough water to make 350 mL of solution is 25.5%.
Explanation:
Given: Volume of solute = 120 mL
Volume of solvent = 350 mL
Now, total volume of the solution is as follows.

Let us assume that 100 mL of solution is taken and the amount of isopropyl alcohol present in it is as follows.

Hence, there is 25.53 mL isopropyl alcohol is present in 100 mL of solution. Therefore, %v/v is calculated as follows.

Thus, we can conclude that the percent by volume of isopropyl alcohol in a solution made by mixing 120 mL of the alcohol with enough water to make 350 mL of solution is 25.5%.
2s 2p
3s 3p 3d
4s 4p 4d 4f
5s 5p 5d 5f
6s 6p 6d
7s 7p
hope it helps
This question is describing two chemical equations whereby the concentration of ammonia has to be determined. The first reaction is between 25.00 mL of ammonia and 50.00 mL of 0.100-M HCl whose excess was neutralized with 21.50 mL of 0.050-M Na₂CO₃ and thus, the concentration ammonia in the cloudy solution was determined as 0.114 M.
First of all we need to go over the titration of the excess HCl with Na₂CO₃ by writing the chemical equation it takes place when they react:

Whereas the mole ratio of HCl to Na₂CO₃ is 2:1 and the volume of the HCl leftover is determined as follows:

Next, we infer that the consumed volume of HCl by the ammonia solution was:

Then, we write the chemical equation that takes place between ammonia and HCl:

Whereas the mole ratio is now 1:1, which means that the concentration of ammonia was:

Learn more:
The concentration required to begin to precipitate PbCl2 for PbCl2 is 0.0216 M.
<h3>
What is molarity?</h3>
Molarity is the measure of the concentration of any solute in per unit volume of the solution.
The reaction is 
The molarity of lead is 0.025 M
The ksp is given 17×10⁻⁵
Now, calculating the concentration
![[Pb^2^+] = 0.025 M.\\Ksp = 1.17 \times 10^-^5\\Ksp = [Pb^2^+] \times [Cl^-]^2\\[Cl^-] = \dfrac{\sqrt{ Ksp}}{[Pb^2^+]} \\\\[Cl^-] = \dfrac{\sqrt{ 0.0000117}}{0.025} \\[Cl^-] = 2.16 \times 10^-^2M.](https://tex.z-dn.net/?f=%5BPb%5E2%5E%2B%5D%20%3D%200.025%20M.%5C%5CKsp%20%3D%201.17%20%5Ctimes%2010%5E-%5E5%5C%5CKsp%20%3D%20%5BPb%5E2%5E%2B%5D%20%5Ctimes%20%20%5BCl%5E-%5D%5E2%5C%5C%5BCl%5E-%5D%20%3D%20%20%5Cdfrac%7B%5Csqrt%7B%20Ksp%7D%7D%7B%5BPb%5E2%5E%2B%5D%7D%20%5C%5C%5C%5C%5BCl%5E-%5D%20%3D%20%20%5Cdfrac%7B%5Csqrt%7B%200.0000117%7D%7D%7B0.025%7D%20%20%5C%5C%5BCl%5E-%5D%20%3D%202.16%20%5Ctimes%2010%5E-%5E2M.)
Thus, the concentration required to begin to precipitate PbCl2 for PbCl2 is 0.0216 M.
Learn more about molarity
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