How can we identify when to use the ideal gas law?


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Jenaye Brelland 2I
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How can we identify when to use the ideal gas law?

Postby Jenaye Brelland 2I » Sun Jan 24, 2021 3:55 pm

How can we identify when to use the ideal gas law?

Saja Kamal 2L
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Re: How can we identify when to use the ideal gas law?

Postby Saja Kamal 2L » Sun Jan 24, 2021 4:05 pm

Hi!

I would say when the problem involves a gas and gives you the values for enough units like pressure, temperature, volume, or moles then you should implement the Ideal Gas Law!

Gwendolyn Hill 2F
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Re: How can we identify when to use the ideal gas law?

Postby Gwendolyn Hill 2F » Sun Jan 24, 2021 4:16 pm

As said above, if a problem gives you multiple elements of the ideal gas law and asks you to solve for one of them, like for pressure for example, then you would use the law. That is also especially true if you're not given a Kp; it means you can't do the ICE table right off the bat.

Audrey Han 3L
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Re: How can we identify when to use the ideal gas law?

Postby Audrey Han 3L » Sun Jan 24, 2021 4:17 pm

Also if you need the molarity of a solution but they've only given you pressure or temp, that's a good sign to use the ideal gas law.

darchen3G
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Re: How can we identify when to use the ideal gas law?

Postby darchen3G » Sun Jan 24, 2021 6:28 pm

You use it when you have all of these variables except one: pressure, volume, moles, temperature

Vivian_Le_1L
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Re: How can we identify when to use the ideal gas law?

Postby Vivian_Le_1L » Sun Jan 24, 2021 6:49 pm

Hi!

We can use the ideal gas law when we are given values for pressure, volume, concentration, and temp except for one. You can use it to solve for the missing variable. For example, in some of the problems we've done, we've used it to convert from concentration to pressure and vice versa.

Jaclyn Schwartz 1I
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Re: How can we identify when to use the ideal gas law?

Postby Jaclyn Schwartz 1I » Sun Jan 24, 2021 11:17 pm

I recommend looking at the problem and see what units you are given, with any problem given for any test! And if the units happen to include pressure, temperature, volume, or moles, then the Ideal Gas Law will probably be the equation for you to use to find the missing variable!

DominicMalilay 1F
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Re: How can we identify when to use the ideal gas law?

Postby DominicMalilay 1F » Sun Jan 24, 2021 11:18 pm

When the equation satisfies PV=nRT in all except one value like pressure, volume, etc, you can use the ideal gas law.

Armen_Isayan_2L
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Re: How can we identify when to use the ideal gas law?

Postby Armen_Isayan_2L » Sun Jan 24, 2021 11:21 pm

Hello! In order to know when to use the ideal gas law it is important to consider which units and variables have been provided in the question. For instance, if the units such as, temperature, volume or mole have been utilized then the ideal gas law is the best solution to find the missing variable

Charlotte Chen 3B
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Re: How can we identify when to use the ideal gas law?

Postby Charlotte Chen 3B » Sun Jan 31, 2021 11:24 pm

Just to add on to the other answers, sometimes you won't directly get given all the variables e.g. you may be given mass instead of mols, but as long as there is sufficient information provided you should be able to calculate the necessary values to complete the expression (in this case you would divide mass by the molar mass to find the no. of mols)

Sarah Salam 1J
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Re: How can we identify when to use the ideal gas law?

Postby Sarah Salam 1J » Sun Jan 31, 2021 11:41 pm

You'll have to look at the equation PV=nRT and see if the question is asking you to solve for one of these variables using what you are given. That would mean you are given or can solve for the rest of the variables.

Ellison Gonzales 1H
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Re: How can we identify when to use the ideal gas law?

Postby Ellison Gonzales 1H » Sun Jan 31, 2021 11:58 pm

Is the unit for partial pressure in the ideal gas law always bar? Or bar and atm?


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