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### Topic: Find the final total pressure of the flask  (Read 281 times)

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#### er4444

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##### Find the final total pressure of the flask
« on: March 12, 2021, 09:01:50 PM »
Gaseous phosphorous trifluoride is prepared by the reaction of phosphine and fluorine:

4PH3 (g) + 3F2 (g) 3PH4F (s) + PF3 (g)

If you mix PH3 and F2 in the correct stoichiometric ratio with an initial total pressure of the reactants of .2atm, then what is the final total pressure in the flask? (Assume T is constant and the reactants have been completely consumed).

#### billnotgatez

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##### Re: Find the final total pressure of the flask
« Reply #1 on: March 12, 2021, 09:36:58 PM »
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#### Orcio_Dojek

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##### Re: Find the final total pressure of the flask
« Reply #2 on: March 13, 2021, 10:34:10 AM »
@er4444

pV = nRT

Volume and temperature doesn't change, so pressure is proportional to quantity of gas.

You have 7 moles of substrats (at pressure = 2 atm), and 4 moles of products (pressure will drop proportionally).

#### mjc123

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##### Re: Find the final total pressure of the flask
« Reply #3 on: March 13, 2021, 03:55:27 PM »
How many moles of gaseous products?

#### billnotgatez

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##### Re: Find the final total pressure of the flask
« Reply #4 on: March 13, 2021, 04:27:19 PM »
... (at pressure = 2 atm)...

... initial total pressure of the reactants of .2atm, ...
« Last Edit: March 13, 2021, 04:38:04 PM by billnotgatez »

#### Orcio_Dojek

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##### Re: Find the final total pressure of the flask
« Reply #5 on: March 13, 2021, 05:19:38 PM »
@mjc123 Only one mol of PF3, sorry.