1. Boyle’s Law

2. What are the 4 variables that describe a gas phase system? Volume Temperature Pressure Amount of gas (in moles)

3. Fixed Mass? You don’t change the number of moles of gas. Don’t add or remove any gas.

4. BOYLE - 1662 Temperature and Amount are constant. Look at relationship between P and V. What happened when I increased the pressure on the syringe? As pressure increases, volume decreases.

5. Image From Tiger Boyle’s Law: 4 step J-Tube experiments

6. Can you explain …. GasVol.mov Popcane.mov

7. TrialPressure (atm)Volume (cm 3 ) 11.00800 22.00400 33.00267 44.00200

8. Scientists plot data because a picture shows relationships better than lists of numbers. There are lots of “pictures” that scientists & mathematicians recognize.

9. Inverse Relationships Graph of 2 variables is a hyperbola.Graph of 2 variables is a hyperbola. Properties:Properties: Relationship is inverse.Relationship is inverse. Product of the 2 variables is a constant.Product of the 2 variables is a constant.

10. TrialPressure (atm) Volume (cm 3 ) Pressure  Volume (atm-cm 3 ) 11.00800 22.00400800 33.00267800 44.00200800 For a given T and amount, pressure X volume always equals the same number – the product is CONSTANT!

11. ComparisonPressure Change Volume Change Trials 1 & 2 1 to 2 800 to 400 2 to 1 Trials 1 & 3 1 to 3 800 to 267 3 to 1 Trials 1 & 4 1 to 4 800 to 200 4 to 1

12. Boyle’s Law - words The volume of a sample of gas is inversely proportional to its pressure, at constant temperature.The volume of a sample of gas is inversely proportional to its pressure, at constant temperature.

13. Boyle’s Law - mathematically P X V = K, a constant V = K/P or P = K/V P 1 V 1 = P 2 V 2 For every point on the hyperbola, P X V = the same constant, K