1. The scientific method and the properties of gases

2. Scientific method
The scientific method is a step by step procedure used by scientists to solve problems.
It includes observation, statement of the problem, hypothesis, experimentation and drawing conclusions such theories and laws.

3. Over the past four centuries, scientists have performed many experiments to understand the common behaviors of gases.
They have observed that a gas's physical condition—its state—depends on four variables: pressure (P), volume (V), temperature (T), and amount of gas.

4. Is not the learning of facts, but the training of the mind to think!
Observation: facts
Education
Is not the learning of facts, but the training of the mind to think!
Albert Einstein
Properties of gases
They adopt the shape of the container.
They occupy all the available volume.
They exert pressure

5. Observation: facts In a gas the magnitudes of
Pressure (Pascal or atmospheres)
Volume (m3 or l)
Temperature (Kelvin)
are connected and if we change one of the others will change.

6. The mass and temperature of the gas don’t change
Experiment
Materials and Procedure
Variable
This is the magnitude ....
Independent
(manipulated)
pressure
I will change during the experiment. It is the only one that I should change.
Dependent
(responding)
volume
It could change as a consequence. I will measure during the experiment.
control
Mass
temperature
These never change
(in this experiment)
manometer
Graduated container
Drag this
Variables are anything that might change or be changed in an experiment.
The mass and temperature of the gas don’t change

7. Data and graphs

8. Simulation of the experiment
Below is a Boyle's Law applet like the syringe we played with in class that allows you to explore the relationship between pressure and volume along with a graph of the data.
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9. When the pressure increases the volume decreases
Drawing conclusions
When the pressure increases the volume decreases
P.V seems to be constant

10. Many scientific laws can be expressed as a mathematical equation
Formulation of laws
The Boyle-Mariotte law states that ……
Many scientific laws can be expressed as a mathematical equation
For the same mass of gas at a constante temperature, when the pressure increases, the volume of the gas decreases, and vice versa

11. Statement of hypothesis
In general, a scientific law is the description of an observed phenomenon. It doesn't explain WHY the phenomenon exists or what causes it.
A hypothesis is a supposition which attempts to explain an observed phenomenon.

12. Theories
The explanation of a phenomenon is called a scientific theory.
In science, a theory is an explanation that generally is accepted to be true but theories can change over time when new data are found.

13. The kinetic Theory of matter- Gases
The kinetic theory explains the Boyle’s Law

14. click image to launch apple

15. When the gas is heated its particles move faster and the energy and number of the collisions with the container wall increase.

16. Science is a collective enterprise

17. The Kinetic Theory of matter
Explain the properties of the different states of aggregation and the change of state.

18. The Kinetic Theory of matter