Ideal Gas Laws
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- skycracker00
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Ideal Gas Laws
Hey guys, I need help with this question. Super confused on it. Here it is:
A balloon is inflated to 4.50 L with Helium, at a particular initial temperature and pressure. (It is tied off.) Now, assume that the temperatures and pressures referred to are always those prevailing inside the balloon.
Then, what would the volume of the balloon be when the pressure is reduced to 1/3 of the initial value and the Kelvin temperature is reduced to 1/2 of the initial value?
I have a feeling of where to start but what are the values of the initial pressure? That part is throwing me off!
If anyone could help, that would be nice.
Thanks
A balloon is inflated to 4.50 L with Helium, at a particular initial temperature and pressure. (It is tied off.) Now, assume that the temperatures and pressures referred to are always those prevailing inside the balloon.
Then, what would the volume of the balloon be when the pressure is reduced to 1/3 of the initial value and the Kelvin temperature is reduced to 1/2 of the initial value?
I have a feeling of where to start but what are the values of the initial pressure? That part is throwing me off!
If anyone could help, that would be nice.
Thanks
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- ChenBeier
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Re: Ideal Gas Laws
Do you know the ideal gas law equation pV = nRT
So you solve for V
Change now p to1/3p and T to 1/2T
So you solve for V
Change now p to1/3p and T to 1/2T
- skycracker00
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- Dhamnekar Winod
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Re: Ideal Gas Laws
So, what is your final answer? What is the ratio of temperature to pressure initially and after making adjustments to their values?
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- skycracker00
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Re: Ideal Gas Laws
I got 0.0250 L. But that was incorrect... not sure what I'm doing wrong?
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- Dhamnekar Winod
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Re: Ideal Gas Laws
Initially, there was 4.5 L volume of Helium gas in the Balloon. So, what is your computed number of mole of Helium gas?
Any science consists of the following process. 1) See 2)Hear 3)Smell,if needed 4)Taste, if needed 5)Think 6)Understand 7)Inference 8)Take decision [Believe or disbelieve, useful or useless, true or false, cause or effect, any other criteria]
- skycracker00
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Re: Ideal Gas Laws
4.50 L x 1 mol He / 22.414 L = 0.200767377 mol (not rounded up)
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Re: Ideal Gas Laws
So, Plugging all the available values in to the formula PV=NRT, we get the ratio of Kelvin temperature to pressure in Bar as 2.696927647572174. Thereafter the new ratio is \(\frac{X}{2} \times \frac{3}{Y}\rightarrow \frac{3X}{2Y}\) where X=Kelvin Temperature , Y= Pressure in Bar.
What are the next computational workings you made to arrive at the final answer of 0.0250 L volume of Helium Gas?
What are the next computational workings you made to arrive at the final answer of 0.0250 L volume of Helium Gas?
Any science consists of the following process. 1) See 2)Hear 3)Smell,if needed 4)Taste, if needed 5)Think 6)Understand 7)Inference 8)Take decision [Believe or disbelieve, useful or useless, true or false, cause or effect, any other criteria]
- skycracker00
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Re: Ideal Gas Laws
Hmm.. I just inserted all the values into the equation V=nRT/P. I think I made a mistake though because I got a different answer to the one I wrote before. My new answer is 0.02746 L. Still wrong..
By the way, how did you get that equation? How did you come up with that thinking?
By the way, how did you get that equation? How did you come up with that thinking?
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- Dhamnekar Winod
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Re: Ideal Gas Laws
Question itself states my thinking. Question says one-half of initial value of temperature(X) and one third of initial value of pressure(Y). So ratio becomes \(\frac{\frac{X}{2}}{\frac{Y}{3}}\).Simplifying, we get \(\frac{3X}{2Y}\). That's it.
Any science consists of the following process. 1) See 2)Hear 3)Smell,if needed 4)Taste, if needed 5)Think 6)Understand 7)Inference 8)Take decision [Believe or disbelieve, useful or useless, true or false, cause or effect, any other criteria]
- ChenBeier
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Re: Ideal Gas Laws
The result is 1.5 x V.
- Dhamnekar Winod
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Re: Ideal Gas Laws
That's correct. thanks. If, i am not wrong, the final volume is 4.04 L of Helium gas in the balloon.
Any science consists of the following process. 1) See 2)Hear 3)Smell,if needed 4)Taste, if needed 5)Think 6)Understand 7)Inference 8)Take decision [Believe or disbelieve, useful or useless, true or false, cause or effect, any other criteria]
- skycracker00
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- ChenBeier
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Re: Ideal Gas Laws
Its wrong. The result is 6.75 l
- Dhamnekar Winod
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Re: Ideal Gas Laws
Oh, Yes. You are correct. 4.04539 is the new ratio of Kelvin temperature to pressure after making adjustments to their initial values. Thanks for pointing out my mistake.
Any science consists of the following process. 1) See 2)Hear 3)Smell,if needed 4)Taste, if needed 5)Think 6)Understand 7)Inference 8)Take decision [Believe or disbelieve, useful or useless, true or false, cause or effect, any other criteria]