ACA

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

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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.

First Name:

Last Name:

Laboratory Section:

In this ACA we will investigate the effect of different variables on the pressure exerted by an ideal gas. To do this investigation we will use a simulation. Clicking on this link above will produce a new page with the simulation. If your browser is not accessorized properly to run this software try downloading the latest version of Java software. That should accessorize the browser so it can run the simulation. You may have to quit and re-start your browser for the software to work properly.

1. Setup the simulation as described in each of the Experiments below and record the pressure.

Table I:

	Exp #1	Exp #2
Gas	Helium	Helium
number of mol	1.00	1.00
Temperature (K)	275	275
Volume (L)	22.65	11.32
Pressure (atm)	atm	atm

2. Which of the following is an explanation for your observation?(Choose one)

there are more collision;

Because the gas particles are traveling at the same average speed and the gas particles have a smaller volume to move around in there is a greater number of collisions with the walls of the container and a corresponding increase in pressure;

Because the average speed of the particles has increased and because the volume of the container is smaller there are more collisions with the walls of the container and a corresponding increase in pressure;

Because the average speed of the particles has increased the force of the collisions with the walls of the container will be greater and a corresponding increase in pressure.

3. Setup the simulation as described in each of the Experiments below and record the pressure.

Table II:

	Exp #1	Exp #2
Gas	Helium	Helium
number of mol	3.00	3.00
Temperature (K)	300	150
Volume (L)	22.65	22.65
Pressure (atm)	atm	atm

3. Which of the following is an explanation for your observation? (Choose one)

Because the average speed of the particles has decreased there are fewer collisions with the walls of the container and a corresponding decrease in pressure;

Because the average speed of the particles has decreased the force of the collisions with the walls of the container is less and there will be a corresponding decrease in pressure; ;

All of the above.

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

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