BCE

Last modified: Wed 12/31/1969 06:00:00 pm BCE

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Answer all of the questions below. If you do not know an answer enter CNA. However, it will help me the most if you answer each question with your best intuition/idea about what would be a reasonable answer.

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In this experiment, a syringe is filled with a gas. The syringe has markings on it to indicate the volume (in mL) of the gas in the syringe. You can choose the gases you wish to investigate from the menu of available gases. Use the volume slidebar to control the volume of the selected gas in the syringe. In this experiment, the initial temperature of each gas is 25.0°C or 298K. The needle on the syringe is plunged into an evacuated flask (a flask with no air or other gas in it - a vacuum) and the gas starts to escape from the end of the needle into the evacuated flask. You can time how long it takes for the syringe plunger to move from the starting point (100.0 mL) to a point lower on the syringe 0.0 mL.

Data Collection:

1. Determine the time required for 100.7 mLs of hydrogen, oxygen and krypton gas to effuse into an evacuated container at 25 degrees Celsius. Complete Table I below with the time in seconds.

Gas Sample	Volume (mLs)	Time (seconds)
Hydrogen (H₂)	100.7
Oxygen (O₂)	100.7
Krypton (Kr)	100.7

Table I.

2. Based on your data answer the following questions

a) Which gas required the smallest amount of time for 100.7 mLs of gas to effuse into an evacuated container?

(hydrogen, oxygen or krypton)

b) Which gas required the largest amount of time for 100.7 mLs of gas to effuse into an evacuated container?

(hydrogen, oxygen or krypton)

3a. Before we do the experiment predict whether it will take more time, less time or the same amount of time for 100.7 mL of xenon gas to effuse into an evacuated container.

(more time, less time, same amount of time)

b) Provide a brief explanationof your reasoning for your claim in Q3a.

4. Do the experiment and measure the time for Xenon. Enter the time into Table II.

Gas Sample	Volume (mLs)	Time (seconds)
Xenon (Xe)	100.7

Table II.

5. How many times faster does a 100.7 mL sample of hydrogen gas effuse compared to oxygen gas?

6. Pick one of the Unknown gases and measure the time required for 100.7 mLs of the gas to effuse into an evacuated container. Enter the Unknown gas you selected and the time required to effuse in Table III. below.

Unknown Gas Sample	Volume (mLs)	Time (seconds)
	100.7

Table III.

7. Is there anything about the questions that you feel you do not understand? List your concerns/questions.

8. If there is one question you would like to have answered in lecture, what would that question be?