1. Gas In A Syringe Investigation
Begin the write up in your lab journal

2. Parts of Syringe Syringe Body Tip Plunger Gas Molecules
Draw and label a syringe in your lab journal
Syringe Body
Tip
Plunger
Gas Molecules

3. 2. Pull the plunger all the way back without separating the pieces.
Activity #1
1. Remove the tip cap.
2. Pull the plunger all the way back without separating the pieces.
Tip cap

4. Notice a sound of moving air
Notice a sound of moving air? More gas molecules are entering the syringe.

5. That is gas molecules being pushed out.
Now push the plunger closed
Hear and feel the air coming out?
That is gas molecules being pushed out.

6. What have we learned? Air is made of gas molecules Air can move
We call moving air wind
Write what you learned

7. 1. Replace the tip Cap on the closed syringe
Activity #2
1. Replace the tip Cap on the closed syringe
2. Try to pull the plunger out and think about what is happening

8. Remove the tip cap from the closed syringe
2. Now, pull the plunger out and think about what is happening

9. What made the difference?
Air can be pulled into the syringe with the cap off but can’t with the cap on
A vacuum was formed and air rushed in to fill the empty space

10. 1. Connect a tube to the end of a syringe with the plunger pulled out.
Activity #3
1. Connect a tube to the end of a syringe with the plunger pulled out.
2. Connect the other end of the tube to a syringe with the plunger pushed all the way in
Syringe 1
Syringe 2
3. Draw and label your set up, do not move any parts

11. Investigation Question: What will happen if I push in the plunger?
Write the following
Investigation Question: What will happen if I push in the plunger?
Prediction: If I push the plunger in on syringe #2, then __________
_______________________________ because_____________________________________________________ .

12. Now try your prediction
Discuss what happened with your partner
Write a conclusion statement
Remember:
Answer the Investigation question.
What did you think would happen?
Was your hypothesis correct?
What really did happen?
Was your results the same as the other students?
Why does this happen?

13. What have we learned?
Air takes up space
Air has volume
Volume means the amount of
space that something takes up
Air will move into a new
space to equalize the pressure
Copy what we learned into your L.J.

14. 1. Remove one syringe from the tube
Activity #4
1. Remove one syringe from the tube
2. Pinch the end of the tube shut and try to push the plunger in. What happens?
Discuss this with your partner
Syringe 1
Syringe 2

15. Air Pressure is always pushing on everything in all directions
The greater the air pressure the greater the push in all directions

16. What have we learned? Air takes up space
Air can be compressed into less
space (smaller volume)
Air has pressure
The more you compress air the
higher the air pressure
Copy Notes
5 molecules
Not
Compressed,
Low pressure
5 molecules
Compressed,
High pressure

17. Air Pressure changes with elevation

18. Nitrogen 78%
Oxygen 21%
As you go up in elevation the number of gas molecules become less compacted and there is less air pressure
Elevation

19. Oxygen is 21% of the air
Air is thinner the higher you go in
elevation
Do you see any problems?