Ideal gas law lab (completed) PDF

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phet.colorado/Open the Phet simulation Gases Intro phet.colorado/sims/html/gases-intro/latest/gases-intro_en.htmland click on the Ideal tab at the bottom.How are absolute pressure, absolute temperature, and volume of an ideal gas related? One way to find out is by holding one of these constant and j...

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Student Directions for Gas Properties: Ideal Gas Laws http://phet.colorado.edu/ Open the Phet simulation Gases Intro https://phet.colorado.edu/sims/html/gases-intro/latest/gases-intro_en.html and click on the Ideal tab at the bottom. How are absolute pressure, absolute temperature, and volume of an ideal gas related? One way to find out is by holding one of these constant and just looking at the relationship between the other two..

1.

Click and drag the pump handle up and down to place gas molecules into the chamber.

2.

Click on the width in the table on the right. This width will be representative of the volume, as we will be changing only one dimension, Record the Temperature, Pressure and “Volume” . T=300K P=3.4atm V(width) =15.0mm 3. 4.

Click on volume in the simulation table labeled” hold constant”. Click and drag upward a little on the heat scale located under the container. You should see flames. Record the temperature and pressure in the following table: Repeat this three more times at different temperatures .Then for each data set, find the ratio P/T T 464K 884K 4640K 8840K

5.

P 5.3atm 10.1atm 53.0atm 101atm

P/T 87.5 87.5 87.5 87.2

What do you notice about this ratio?

It stays constant 6.

Cool the molecules down by clicking and dragging down on the heat scale .You should see ice appear. See if you can get the system back to its original temperature and pressure that you recorded in #2.

If the ratio P/T is constant we can say that absolute pressure is proportional to absolute temperature.

5/12/2021 Loeblein Thanks to Sarah Borenstein’s lesson on PhET Teacher’s Activity Database

Student Directions for Gas Properties: Ideal Gas Laws http://phet.colorado.edu/ 7.

Now click on Pressure ↨V in the “hold constant” simulation table. Increase the temperature as you did before, but this time record the temperature and volume for four different temperatures.

Note: Pressure could not be held constant because volume too large message appeared, so I set the volume to 5.0mm before beginning this step T 350K 450K 600K 750K 8.

V (width) 5.8mm 7.5mm 10.0mm 12.5mm

V/T 60.3 60.0 60.0 60.0

What do you notice about the ratio V/T in each case? Write a mathematical statement about the relationship of volume and absolute temperature.

The change in T/Change in V = 60 9.

Next, let’s hold the absolute temperature constant. A handle should appear on the left side of the container. Click and drag the handle bar to decrease the width of the container. Record the “Volume” and the pressure at four different widths in the table below:

10.

What happened to the pressure as the volume decreased?

11.

Multiply P and “V” together for each data set. V(width) 15.0mm 12.5mm 10.0mm 5.0mm

P 9.0atm 10.8atm 13.4atm 26.9atm

PV 1.66 1.16 0.75 0.19

12. What do you notice about the product of P and “V”? The product of P and V decreases when V decreases

When the product of P and V is constant, we say that P is inversely proportional to V

5/12/2021 Loeblein Thanks to Sarah Borenstein’s lesson on PhET Teacher’s Activity Database

Student Directions for Gas Properties: Ideal Gas Laws http://phet.colorado.edu/

What would happen if we let all three values change, holding nothing constant (except the number of molecules)? 13.

Click “nothing” in the simulation table. Then change the state of the system by either changing the volume or the temperature (or both!) Record four different results in the table below. Then see if you can come up with a formula using products and ratios that produce a constant number like the previous tables. Write your formula and test it to see if it stays constant for each of your data sets.

T

V (width)

P T =constant

300K 300K 300K 300K

5.0mm 5.5mm 6.0mm 6.5mm

10.7atm 9.7atm 8.7atm 7.7atm

0.47 0.57 0.68 0.84

Using your results, explain each of the following scenarios. a.

Explain why bicycle tires seem more flat in the winter than in summer.

Lower temperatures cause gas molecules to move slower, thus decreasing pressure b. Explain why a can of soda pop explodes if left in the hot sun. Higher temperatures cause gas particles to move slower, thus increasing pressure and causing the soda to explode c.

A rigid container filled with a gas is placed in ice (ex. nalgene bottle). What will happen to the pressure of the gas?

The pressure of the gas will decrease d. Why must we use an absolute temperature scale for the ideal gas law?

5/12/2021 Loeblein Thanks to Sarah Borenstein’s lesson on PhET Teacher’s Activity Database

Student Directions for Gas Properties: Ideal Gas Laws http://phet.colorado.edu/ To avoid any conversion errors

5/12/2021 Loeblein Thanks to Sarah Borenstein’s lesson on PhET Teacher’s Activity Database...