A flask of known volume was filled with air to a pressure of 3.6atm. This flask was then attached to an evacuated flask of known volume and the air was allowed to expand into the flask. The final pressure of the air (in both flasks) was 2.7atm and the volume of the second flask was 4.9L. Calculate the volume of the first flask.
I understand this is Boyle's Law, but I keep getting 3.6375L. However the real answer is ~14.7L. Dividing the real answer by the answer I got is exactly 4. I do not understand the concept of evacuated flask, as my intro Chemistry teacher never taught me that, nor my current Chemistry teacher.
p₁ v₁ = p₂ v₂
3.6 * v = 2.7 * (v + 4.9)
.9 v = 2.7 * 4.9 ... v = 14.7
the evacuated flask means that no additional air was introduced into the system ... just a volume increase with a corresponding pressure decrease
How did the left side of the equation went from 3.6*V to .9V?
distributing on the right
... 3.6 v = 2.7 v + (2.7 * 4.9)
subtracting 2.7 v
... .9 v = 2.7 * 4.9
p₁ v₁ = p₂ v₂
3.6 * v = 2.7 * (v + 4.9)
You are right to here. The next step you failed to multiply every thing inside the parentheses by 2.7.
3.6v = 2.7v + (2.7*4.9)
3.6v = 2.7v + 13.2
3.6v-2.7v = 13.2
0.9v = 13.2
v = 14.66 which rounds to 14.7
To solve this problem using Boyle's Law, we need to understand the concept of an evacuated flask.
An evacuated flask is a flask that has been completely emptied of any gas, creating a vacuum inside. In this experiment, the second flask starts off as evacuated, meaning there is no gas initially present in it.
Boyle's Law states that the pressure and volume of a gas are inversely proportional, as long as the temperature remains constant. Mathematically, this can be represented as P1V1 = P2V2, where P1 and V1 are the initial pressure and volume of the gas, and P2 and V2 are the final pressure and volume of the gas.
Given the initial pressure (P1 = 3.6 atm), final pressure (P2 = 2.7 atm), and volume of the second flask (V2 = 4.9 L), we can rearrange the equation to solve for V1.
P1V1 = P2V2
V1 = (P2V2) / P1
Plugging in the values we have:
V1 = (2.7 atm * 4.9 L) / 3.6 atm
V1 ≈ 3.683 L
So, the volume of the first flask is approximately 3.683 L, not 3.6375 L as you calculated. The discrepancy between your answer and the correct answer is likely due to rounding errors or calculation mistakes.
However, if the correct answer is indeed ~14.7 L, then there may be other factors involved in the experiment that were not provided in the question. It's important to consider all the given information and its relevance to the problem at hand.
If you have any further questions, feel free to ask!