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Chemistry Forums for Students => High School Chemistry Forum => Topic started by: Des on February 10, 2019, 10:31:02 PM

Title: Questions Regarding Partial Pressure, Ideal Gas Law, & Wet-Dry Gases
Post by: Des on February 10, 2019, 10:31:02 PM
Hello, I have a few questions regarding the topics listed in the subject line. These questions come from my chemistry assignment, and I'm still unfamiliar with how to do them. I understand how to do certain steps, but I don't know what steps and in what process to do them. Thank you in advance for helping me with these questions.


10.0 grams of nitroglycerine is decomposed via explosion. The total pressure is 1.45 atm at 523 °C. Determine the partial pressure of each of the products AND the total volume of gas produced by the explosion.


If 60.0L of wet nitrogen is collected over water at 40.0 °C when the atmospheric pressure is 1.00 atm, what is the partial pressure of the nitrogen? (Vapor pressure of water at 40.0 oC is 0.0727 atm)


45.0 mL of wet argon gas is collected over water at 729.3 mmHg and 25.0 °C. What would be the volume of this dry gas at standard conditions? The vapor pressure of water is 0.0313 atm.


50.6 mL of a gas is collected over water at 18.0 °C and 755.5 mmHg pressure. What is the volume of dry gas at STP? At 18.0 °C, the vapor pressure of water is 0.0203 atm.
Title: Re: Questions Regarding Partial Pressure, Ideal Gas Law, & Wet-Dry Gases
Post by: Borek on February 11, 2019, 03:28:09 AM
You have to show your attempts at solving the problem, this is a forum policy.

10.0 grams of nitroglycerine is decomposed via explosion. The total pressure is 1.45 atm at 523 °C. Determine the partial pressure of each of the products AND the total volume of gas produced by the explosion.

Hint: start with a reaction equation.
Title: Re: Questions Regarding Partial Pressure, Ideal Gas Law, & Wet-Dry Gases
Post by: Vidya on February 11, 2019, 07:33:57 PM
Borek is right ...start with reaction for part 1
What do you know about partial pressures or Dalton's partial pressure law ?
depending on information  given in the question you can use any of these equation

P (dry gas) = P (total) -P water (at given T)
Partial pressure of gas A = P(total) × XA
XA -->mole fraction of the gas in the mixture
PA = nART/V
V is total volume of the gas
R is universal gas constant
T is temperature