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

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

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

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

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.

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

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

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

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

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

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_____________________________________________________ .

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?

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.

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

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

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

Air Pressure changes with elevation

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

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