A 275-mL flask contains pure helium at a pressure of 752 torr. A second flask with a volume of 475 mL contains pure argon at a pressure of 722 torr. If we connect the two flasks through a stopcock and we open the stopcock, what is the partial pressure of argon?

Video transcript

Welcome back everyone to flasks are connected via a stop cock, A 2 50 millimeter flask containing zen on at 708 Tour and a 4 millimeter flask containing neon at 8 20. To tour the stop cock is opened and the gasses are allowed to mix, calculate the partial pressure of neon. Let's note that the prompt tells us that our neon and ar zen on mix and so they will not react. And that's because the prompt does not mention any evidence of a type of reaction occurring. And so for this example, we want to recall our formula for Boyle's law, which relates initial pressure times initial volume equivalent to final pressure times the final volume for our gasses. So we need to isolate for P. Two being our final pressure or final partial pressure of neon. And so What we would have is, or rather we want to divide both sides by V2, canceling that out on the right hand side so that we would have to our final pressure for neon is equal to the initial pressure times the initial volume divided by final volume. And so let's note down the variables that we know. We know that the initial pressure of neon According to the prompt is 822 tour and this is before the Gasses Mix. So before mixing with Xenon. Now, for the initial volume We are given from the prompt, a volume of 450 ml. Now the volume at the final point of our prompt Which describes our mixed gasses, meaning the final volume V two. We would consider 450 ml plus our volume of Xenon being 250 ml. And so this total gives us v. two as 700 ml for the mixed gasses. Now, with these variables written out, let's plug in what we know to solve for the final partial pressure of neon. And so what we would find is that for P. One as we stated, that's 8 22 Tour for just neon gas without sin. In then for the initial volume, just for the volume of neon before it's mixed with Zenon, it's given as 4 50 mL as we stated above. And then in our denominator, our final volume is the total of our mixed gasses which we confirmed to be 700 mL. And so canceling out our units of milliliters were left with units of tour for our pressure and I'm sorry this says Tour. So we're going to find that our final partial pressure of Neon yield a result of 528. tour which we want to be As As 528 tour. And this would be our final answer as our partial pressure of neon gas in this example. So our final answer highlighted in yellow corresponds to choice be in the multiple choice. I hope everything I reviewed was clear. If you have any questions, please leave them down below and I'll see everyone in the next practice video.