Flask A contains 100 milliliters of a solution with a pH of 5. After you add 100 milliliters of a solution from Flask B, the pH rises to 7. What was the pH of the solution in Flask B?

I would do this.

pH = 5 means (H^+) - 1E-5 M.
mols (H^+) in flask A = M x L = 1E-5*0.1 = 1E-6. So to make a pH = 7 we must exactly neutralize the acid to give pure H2O which has a pH of 7.00. So we need exactly 1E-6 mols OH^- in flask B and that in 100 mL (0.1L) is (OH^-) = 1E-6/0.1 = 1E-5M OH^- which has a pOH = 5. Since pH + pOH = pKw = 14, then pH must be 9.

I worried about the dilution factor (100 mL becoming 200 mL final volume) and how to adjust for that until I finally realized that we are using H^+ to neutralize OH^- which makes H2O and adding 100 mL H2O to another 100 mL H2O just gives 200 mL of H2O but still with a pH of 7. For whatever it's worth, when you've taken more chemistry you will find that activity coefficients will change the pH of water with a salt in it to less than pH 7. I have ignored any effects due to activity instead of concn. That's makes it MUCH more complicated.

Well, well, well, pHew! Looks like we've got ourselves a pH puzzle here! So, let's break it down like a comedian breaking down a joke.

We have Flask A with a pH of 5, and we add Flask B to it, resulting in a pH of 7. Now, we want to know what the pH of Flask B was.

Let's imagine Flask A is like a sour lemon, all acidic and stuff, with a pH of 5. And then comes along Flask B, like a superhero with a pH-neutralizing cape. It swoops in and raises the pH to 7, saving the day!

Now, to find out the pH of Flask B, we need to think mathematically. Since we added equal parts of Flask B to Flask A, we can guess that Flask B must have been right in the middle of pH 5 and pH 7, trying to restore the balance.

If Flask B were a person, it would be like walking a tightrope between being too acidic and too basic. It's like trying to stay neutral in a world full of strong opinions, you know?

So, to be precise, the pH of Flask B would be 6! It played the role of the pH-neutral superhero, saving the day and keeping everything balanced.

Remember, though, this is just a guess based on equal parts of solutions being added. Just like a comedian, I take my guesses with a pinch of salt and a dash of humor. So, take it with a grain of salt, okay? Keep laughing, my friend!

To find the pH of the solution in Flask B, we can use the concept of dilution and the change in pH.

1. We know that the initial solution in Flask A has a pH of 5.
2. When we add 100 milliliters of a solution from Flask B, the pH of the mixture rises to 7.

To calculate the pH of the solution in Flask B, we can use the formula:

(pH_initial * V_initial + pH_added * V_added) / (V_initial + V_added) = pH_final

where:
- pH_initial is the initial pH of the solution in Flask A
- V_initial is the volume of the solution in Flask A
- pH_added is the pH of the solution added from Flask B
- V_added is the volume of the solution added from Flask B
- pH_final is the final pH after the two solutions are mixed

Substituting the given values into the formula, we can solve for the pH of the solution in Flask B:

(5 * 100 + pH_added * 100) / (100 + 100) = 7

Simplifying the equation:

(500 + pH_added * 100) / 200 = 7

Multiplying both sides by 200:

500 + pH_added * 100 = 1400

Subtracting 500 from both sides:

pH_added * 100 = 900

Dividing both sides by 100:

pH_added = 9

Therefore, the pH of the solution in Flask B is 9.

To determine the pH of the solution in Flask B, we can use the concept of dilution and the fact that pH is a logarithmic scale.

Step 1: Determine the hydrogen ion concentration ([H+]) in Flask A
Since the pH of Flask A is 5, we can calculate the hydrogen ion concentration using the formula: [H+] = 10^(-pH).
[H+] = 10^(-5) = 0.00001 moles/L.

Step 2: Determine the concentration of [H+] in Flask B after dilution
Since Flask B is added in equal volume to Flask A, the total volume after mixing is 200 mL (100 mL from Flask A + 100 mL from Flask B).
Since the overall volume doubled, the concentration of [H+] in Flask B is halved.
Thus, the new concentration of [H+] in Flask B = 0.00001 / 2 = 0.000005 moles/L.

Step 3: Calculate the pH of Flask B
To calculate the pH of Flask B, we need to reverse the process from step 1. The formula to calculate pH from [H+] is: pH = -log[H+].
pH = -log(0.000005) ≈ 5.3.

Therefore, the pH of the solution in Flask B is approximately 5.3.