Chemistry set 2 Flashcards
What do ‘gas laws’ do?
Gas laws describe how gas will behave.
Why are scientific laws not like legal laws?
Scientific laws describe how things behave, they do not give explanations.
What is needed to provide an explanation for a scientific law?
A theory provides and explanation for a scientific law.
Name the theory to explain how gasses behave.
Kinetic Molecular Theory of Gasses explains how gas behaves.
What is the first assumption of the gas theory?
- Particles (atoms or molecules) are constantly moving in straight lines until they collide with other particles or walls of their container
What is the second assumption of the gas theory?
- There is no loss of energy when a particle collides with another particle or the wall of the container.
What is the third assumption of the gas theory?
- the volume of the particles themselves is so small compare to the volume of the space they occupy that it is considered to be negligible (can be ignored)
What is the fourth assumption of the gas theory?
- the are no forces of attraction between particles because they are so far away from each other when they are in the gas state.
What is elastic collision?
Elastic collision is when particles collide and do not lose energy, this is only in the world of molecules.
What is inelastic collision?
In our world, when things collide they lose energy and slow down due to friction.
What does the Gas theory explain?
The gas theory explains pressure
What is pressure?
Pressure is the force of many molecules against the walls of a container.
What kind of pressure to molecules put on a container?
Molecules have an outward pressure on containers.
What happens if the pressure becomes stronger than the container?
An explosion happens when the pressure of the gas is greater than the strength of the container.
What kind of energy does gas have?
Gas has kinetic energy. (moving energy)
When the kinetic energy of a gas changes, what also changes?
The temperature rises if the gas’s kinetic energy increases.
In what three ways do we measure gas?
Volume, temperature and pressure are used to measure gas.
What is volume?
Volume is the amount of space the gas takes up.
How is gas volume measured?
Gas is measured in capacity units, milliliters (mL) and liters (L), or large volumes in kilolitres (kL)
Why are both Fahrenheit and Celsius based on water temperature?
Originally people were interested in knowing when water changes state, freezing and boiling points.
Do Fahrenheit and Celsius work well for gas?
No, because at zero gas particles are still moving.
Who was Anders Celsius?
Anders Celsius was a Swedish astronomer and physicist who invented celsius.
What is the absolute temperature scale?
The absolute temperature scale was created to show when gas particles stop moving.
What is another name for the absolute temperature scale?
Kelvin scale, after its creator Lord Kelvin of England.
