TODAY:
FOLDERS: Opening and Closing Exercise
New Assignment: Worksheet on Pressure/Volume
CALCULATORS
HEADPHONES AND ELECTRONICS AWAY UNTIL INSTRUCTED
REMINDER:
Worksheet on Pressure is due on the 26th, beginning of class.
DAILY POINTS
• As of today, you will have the opportunity to earn daily points.
5 points a day will be available for meeting classroom
expectations:
• 1. Phones /headphones/electronics put away when asked. And
they stay away.
• 2. Not sleeping in class.
• 3. Doing the opening/closing exercises and participating in class.
• 4. Being on time and ready to work
• 5. No side conversations.
OPENING EXERCISE
• Why does a helium balloon
explode when it reaches the upper
atmosphere?
PREDICTING GAS BEHAVIOR
LESSON OBJECTIVES:
Describe and apply the relationship between pressure and volume of a
gas sample at constant temperature.
TODAY’S LESSON OBJECTIVES:
Practicing using Boyle’s law to solve problems.
CONSTANTS
One last piece of Boyles Law.
When temperature and moles of gas are constant, the product of the
volume and pressure will be constant.
You can use this idea to check your answers as you work through the worksheet.
P₁ V₁ = P₂ V₂
↓ = ↓
CONSTANTS
We did this problem yesterday:
If initially a gas sample occupies a volume of 8.0 mL and exerts a pressure
of 1.0 atm, how would the pressure of the gas sample change if its volume
were increased to 10.0 mL?
1 atm 8.0 mL= P₂
10.0 mL
CONSTANTS
We did this problem yesterday:
If initially a gas sample occupies a volume of 8.0 mL and exerts a pressure
of 1.0 atm, how would the pressure of the gas sample change if its volume
were increased to 10.0 mL?
1 atm 8.0 mL= .8 atm
10.0 mL
CONSTANTS
When you have found the missing factor, you can re-arrange the formula
back to it’s original arrangement. Multiply each side; the products should
match.
(1 atm) (8.0 mL)= (0.8 atm) (10.0 mL)
↓
=
↓
8 atm mL
8 atm mL
ONE LAST THING…
As a note…. Boyle’s law can also be written using all letters instead
of numbers.
Pᵢ Vᵢ = Pf Vf
The “i” stands for “initial” and the “f” stands for “final”
WORKSHEETS IN FOLDERS
• These are a classroom assignment, so won’t be turned in,
but you will earn points
CLOSING EXERCISE
What would happen to
the size of a helium
balloon if you took it to
the bottom of the ocean?