Pressure in an open beaker

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Maya Gollamudi 1G
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Joined: Thu Jul 25, 2019 12:15 am

Pressure in an open beaker

Postby Maya Gollamudi 1G » Sat Feb 01, 2020 5:21 pm

In an open beaker system, how do we know that the system is at constant pressure?

Daniel Chen 2L
Posts: 101
Joined: Fri Aug 30, 2019 12:15 am

Re: Pressure in an open beaker

Postby Daniel Chen 2L » Sat Feb 01, 2020 5:51 pm

Since the beaker is an open system, you can assume that the pressure is whatever the atmospheric pressure is. Unless you are somehow constantly changing in elevations or something else, I think you can otherwise assume that the pressure is constant?

Altamash Mahsud 1I
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Joined: Fri Aug 09, 2019 12:16 am

Re: Pressure in an open beaker

Postby Altamash Mahsud 1I » Sat Feb 01, 2020 6:25 pm

For an open beaker system, the beaker is open to the atmosphere, therefore the system and surroundings have the same pressure, in this case, it is the atmospheric pressure.

Tiffany Chao 2H
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Joined: Fri Aug 09, 2019 12:17 am

Re: Pressure in an open beaker

Postby Tiffany Chao 2H » Sat Feb 01, 2020 6:29 pm

Pressure should be the pressure of the atmosphere

Sartaj Bal 1J
Posts: 101
Joined: Thu Jul 25, 2019 12:17 am

Re: Pressure in an open beaker

Postby Sartaj Bal 1J » Sat Feb 01, 2020 6:39 pm

All of the above answers are correct. Something that I found helpful to remember regarding the differences between a system and its surroundings is the ocean analogy. Spilling half a liter of water into the ocean doesn't affect its pressure.

Nicholas_Gladkov_2J
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Joined: Sat Aug 17, 2019 12:17 am

Re: Pressure in an open beaker

Postby Nicholas_Gladkov_2J » Sat Feb 01, 2020 6:56 pm

Maya Gollamudi 1G wrote:In an open beaker system, how do we know that the system is at constant pressure?



The pressure in an open beaker is constant.

The surrounding system is so large that your reaction will have virtually no influence on the surrounding system's pressure; as a result, your pressure is constant.

305385703
Posts: 102
Joined: Thu Jul 11, 2019 12:15 am

Re: Pressure in an open beaker

Postby 305385703 » Sat Feb 01, 2020 11:08 pm

Adding moles of gas to the atmosphere does not change its overall pressure in a way that's measurable. Therefore, an open system has a constant external pressure.

Andres Merlos 2L
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Joined: Wed Sep 18, 2019 12:17 am

Re: Pressure in an open beaker

Postby Andres Merlos 2L » Sun Feb 02, 2020 5:50 pm

An open beaker system allows the exchange of pressure between its surroundings and the system. Since the atmosphere is relatively large, the pressure of the beaker will not have an effect on it, almost like a drop-in-the-bucket type deal. We can then infer a constant pressure because of this.

MeeraBhagat
Posts: 95
Joined: Sat Aug 24, 2019 12:15 am

Re: Pressure in an open beaker

Postby MeeraBhagat » Sun Feb 02, 2020 6:00 pm

In an open beaker, the system is at constant pressure because there is no volume to contain any increase or decrease in pressure, and the pressure of the system will be the same as the atmosphere.

Angela Wu-2H
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Joined: Fri Aug 30, 2019 12:16 am

Re: Pressure in an open beaker

Postby Angela Wu-2H » Sun Feb 02, 2020 6:08 pm

Is the constant pressure being referred to by everyone just 1 atm? Or will the actual pressure be given with the question?

Nathan Rothschild_2D
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Joined: Fri Aug 02, 2019 12:15 am

Re: Pressure in an open beaker

Postby Nathan Rothschild_2D » Sun Feb 02, 2020 8:27 pm

Actual pressure should be given. If it is not given it will cancel out and not be necessary for calculations

Samuel Tzeng 1B
Posts: 103
Joined: Sat Aug 24, 2019 12:15 am

Re: Pressure in an open beaker

Postby Samuel Tzeng 1B » Sun Feb 02, 2020 8:28 pm

Pressure in an open beaker is always constant since there isn't a volume to drop or increase pressure

J_CHEN 4I
Posts: 54
Joined: Tue Nov 14, 2017 3:01 am

Re: Pressure in an open beaker

Postby J_CHEN 4I » Sun Feb 02, 2020 8:36 pm

The pressure in an open beaker would be the pressure of the surroundings. The surroundings is typically at a constant pressure.


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