In this diagram, the springer is open. The air molecules are spread out throughout the syringe. The black dots are representing the air molecules in the syringe and

they are flowing in and out of the syringe.

The syringe is plunger is half way into the syringe. The black dots still represent the air molecules. The

molecules are the same amount as the first picture, but they are more compact. The air molecule are still out of the syringe because they are flowing in and out of the syringe.The red arrow in the diagram is showing the

force of the pressure that is being resulted.

As you pull the plunger open, the air particle start to enter the syringe again. The black dots are still

representing the air particles and the particles are entering the tip of the syringe one by one. The red arrow represents the force and resulting pressure.

The particle of air are shown in black. The syringe have been fully closed. Because the syringe is closed, the air particles have no where to go. They have been pushed out of the syringe and are flowing around the tip of the

syringe trying to enter the syringe again.

When the plunger of the syringe is at the bottom of the syringe, the marshmallow in side it is able to move all around. It is restricted from leaving the

syringe, but it can move from the plunger to the tip of the syringe.

When I started to push the plunger toward the tip of the syringe, I had my hand over the tip. It was

difficult to press the plunger because the pressure was so strong inside because the pressure particles

could not exit the syringe. The marshmallow kept getting forced to the top of the syringe.

In this picture, the marshmallow is pushed to the tip of the syringe. The pressure particles in the syringe are

compacted into the tip of the syringe. The particles are around the marshmallow and the particles are floating

in and out of the syringe.

As I started to pull the plunger out of syringe, I had my hand over the tip. As I kept pulling the plunger, the marshmallow started to expand. It got bigger and bigger as I kept pulling away. The red arrow represents the pressure flow during this picture.