Chemistry 11 grade

Question

A helium filed balloon has pressure of 101kPa and a temperature of 23C. It is placed in a freezer where the temperature is 0C. If the volume of the ballo0n remains constant, what is the new pressure of gas in the ballo0n?

The volume of a gas filled balloon is 30.0 L at 313K and 1.5 atm, What would the volume be if the balloon was changed to STP?

A sample of compressed methane has a volume of 0.648L at a pressure of 503kPa at 75.0C. What pressure would it be compressed to in order to have a volume of 0.216L and a temperature of 50.0 C?

What pressure will be needed to reduce the volume of a 77.4 L sample of helium at 98.0 kPa to volume 60.0L?

Answer 1

Hello Lesya,

I will focus on the first question. Since the volume of the balloon remains constant in this problem, you can use Gay-Lussac's Law to find the final pressure. Gay-Lussac's Law states that:

P₁/T₁ = P₂/T₂

In order to solve for P₂, you have to plug in the values for P₁, T₁, and T₂ and then do some multiplication/division. Remember that you need to convert degrees Celsius to kelvins.

Sincerely,

Michael