Chap 9 Kinetic Model of Matter Flashcards
What are the 3 states of matter?
Solid, liquid, gas.
What are the properties of a solid?
A solid has a fixed shape and volume and is normally hard and rigid. It has a high density and is incompressible.
What are the properties of a liquid?
A liquid has a fixed volume but does not have a fixed shape. It has a high density and is incompressible.
What are the properties of a gas?
A gas has no fixed shape or volume. It has a low density and is compressible.
What is the Kinetic Model of Matter?
All matters are made up of tiny particles called atoms or molecules (groups of atoms joined together). These particles are in constant random motion and the continuous motion of these particles is known as the kinetic model of matter.
Describe the arrangement and movement of particles in a solid?
Particles are closely packed together, usually in a regular pattern, occupying minimum space which results in high densities. Particles are held in position by very strong intermolecular bonds and hence vibrate about fixed positions only. Hence solids have fixed volumes and shapes.
Describe the arrangement and movement of particles in a liquid.
Particles are randomly arranged and are only slightly further apart as compared to that of solids which results in liquids having relatively high densities. Particles are free to move about but are confined within the vessel containing it. Hence, liquids have fixed volume but will take the shape of the vessel containing it.
Describe the arrangement and movement of particles in a gas.
Particles are very far apart, randomly arranged and will occupy any available space which results in gases having very low densities. Particles move about randomly at high speeds as they have very little attraction between them. Hence, gases have no fixed volume and shape, and why they are highly compressible.
What does brownian motion refer to?
Brownian motion refers to the random irrregular and jerky motion of smoke particles in air.
How will a higher temperature effect the motion of smoke particles?
At a higher temperature, the motion of smoke particles will become more vigorous and agitated. This is because the air molecules are bombarding the smoke particles more vigorously and frequently. This is because the air molecules have greater speeds at higher temperatures as the increase in thermal energy is converted to kinetic energy of the air molecules, causing it to move faster.
Why do gases exert a pressure in a container?
Moving gas molecules collide with the surface of the wall of the container and exert an average force on it. Since pressure is the force exerted per unit area, we can say that the gas molecules exert pressure on the walls of the container.
What is the relationship between gas pressure and temperature?
As temperature increases, gas molecules will gain speed. The gas molecules will then bombard the walls of their container more vigorously and frequently which causes an increase in the average force exerted on the walls of their container. Since pressure is force exerted per unit area, pressure will increase.
What is the relationship between volume of a gas and temperature?
When a gas is heated, the gas molecules will move at higher speeds. This results in more frequent and violent collisions between the gas molecules and the walls of their container. Hence pressure increases but to keep pressure constant, the gas will expand if it can.
