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Bell Work1.) Complete the “bell work” section on your lab worksheet.2.) Please get out a BLANK LINED PAPER to turn in at the end of the period!

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Marshmallows Under Pressure Lab

Exploring the Relationship between Pressure & Volume

~ Boyle’s Law

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ObjectiveStudent will write a paragraph using his/her observations to

justify a claim about the relationship between

pressure and volume of a gas using new vocabulary.

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Exploring changes of pressure

Opening a soda bottle

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Changes of Pressure

Opening a soda bottle

2) For the gas inside the bottle, was the pressure increased or

decreased?

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Changes of Pressure

Pumping up a tire

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Changes of Pressure

Pumping up a tire

3) For the gas inside the tire, was the pressure increased or

decreased?

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Changes of Pressure

Pushing plunger on syringe

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Changes of Pressure

Pushing plunger on syringe

4) When I pushed the plunger down, was the pressure inside the syringe increased or decreased?

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Pressure(FOR YOUR NOTES!)

The science definition of pressure:Pressure is the force exerted per

unit area on a surface. It is the exertion of force upon a

surface by an object, fluid, gas etc., in contact with it.

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PressureWith your partner:

Share your answers to questions 2, 3, and 4.

Then answer:5) What is exerting the force on the inside surface of the bottle, tire, syringe?

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Pressure(FOR YOUR NOTES!)

Pressure & Gas: Gases exert pressure by colliding with each other and the surfaces of their containers. Increased pressure means more collisions are occurring, decreased pressure means fewer collisions are occurring.

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Review: Volume

Discuss with your partner:What is volume?

Does gas have volume?

Volume: the quantity of three-dimensional space occupied by

a liquid, solid, or gas.

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Gas Vocabulary(FOR YOUR NOTES!)

Inverse relationshipIf two things have an inverse

relationship, one will decrease if the other increases .

For example: number of students who take the school bus and number of cars parked in the student parking lot

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Gas Vocabulary(FOR YOUR NOTES!)

Direct relationshipIf two things have a direct

relationship, one will increase if the other increases .

For example: happiness and number of tacos consumed

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Pressure and Volume

We will explore the relationship between pressure and volume by observing how a

marshmallow changes with increasing/decreasing pressure.

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But First!

As you observe the marshmallow changing, think about how the volume of gas

inside the marshmallow is changing!

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Directions:1) Place one marshmallow at a time in the

air piston.2) Insert plunger and push down until it is

slightly above marshmallow3) Hold finger over piston opening4) Pull plunger out and push plunger in to

change the pressure5) THINK ABOUT THE VOLUME OF GAS

INSIDE THE MARSHMALLOW!

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The relationship between pressure and volumeWrite a paragraph that answers:

• How did you increase the pressure on the marshmallow’s gas and how did it affect the marshmallow?

• How did you decrease the pressure on the marshmallow’s gas and how did it affect the marshmallow?

• Based on your observations, what can you claim about the relationship between pressure and volume of a gas?

You must use your NEW VOCABULARY: inverse relationship, force, collisions, increase/decrease