Tutors: thanks for your help.

Is this how this problem is solved ?

A sample of Xenon gas at 20degrees celcius and 0.570atm is cooled to a pressure of 0.100atm. If the volume remains constant what is the final temperature in degree celcius?

Solution: Using Gay-Lussac's Law to find T2 or final temperature.

T2=P2T1/P1
=(0.100atm)(293kelvin)/0.570atm
=51.4kelvins
=51.4k - 273k
= - 222degrees celcius ??

And last question

If 0.105mol of He gas occupies a volume of 2.35L,what volume would 0.337 mol of He occupy?

Solution:
1 mole of a gas at STP = 22.4L

So, 0.337mol He * 22.4L/1 mol He = 7.55L.

Have a Good Evening.

Both answers are correct.

Tutors: You're welcome! I'm glad I could help. Let me explain how you arrived at the correct answers for both problems.

For the first problem, you correctly identified that the problem can be solved using Gay-Lussac's Law. According to Gay-Lussac's Law, the ratio of the initial and final temperatures is equal to the ratio of the initial and final pressures, assuming the volume is kept constant. The formula for Gay-Lussac's Law is:

T2 = P2 * (T1 / P1)

To solve for the final temperature (T2), you substituted the given values into the formula. The initial pressure (P1) is 0.570 atm, the final pressure (P2) is 0.100 atm, and the initial temperature (T1) is 20 degrees Celsius (or 293 Kelvin).

Plugging in the values, you correctly calculated:

T2 = (0.100 atm) * (293 K) / (0.570 atm) = 51.4 Kelvin

To convert it back to degrees Celsius, you subtracted 273 Kelvin from 51.4 Kelvin, resulting in -222 degrees Celsius. So, your final answer of -222 degrees Celsius is correct.

For the second problem, you are using the concept of the molar volume of gases at standard temperature and pressure (STP). At STP, 1 mole of any gas occupies a volume of 22.4 liters.

In this problem, you are given 0.105 moles of helium gas occupying a volume of 2.35 liters. To find the volume of 0.337 moles of helium gas, you applied the concept of molar volume. You set up the following proportion:

(0.337 mol / 1 mol) = (V2 / 22.4 L)

Solving for V2 (the volume of 0.337 moles of helium gas), you multiplied both sides by 22.4 L and got:

V2 = 0.337 mol * 22.4 L / 1 mol = 7.55 L

Therefore, you correctly found that the volume of 0.337 moles of helium would be 7.55 liters.

Great job! If you have any more questions, feel free to ask.