The Particle Model & particle movement Flashcards
How does the particle model explain how solids and liquids are incompressible?
The particles in solids and liquids cannot be pushed closer together because they are so closely packed that there is almost no space between them.
How does the particle model explain how liquids, solids and gases expand and contract?
Heating causes the particles to vibrate faster, making them spread further apart and causing the solid to expand. Cooling slows down vibrations and the opposite happens.
How does the particle model explain how liquids flow to take the shape of the bottom of their container?
Bonds are strong but loose enough to let the particles in a liquid to slip over one another.
How does the particle model explain gases often being invisible?
Particles in a gas are spread so far apart that you cannot see the gas.
How does the particle model explain how gases can be compressed?
Particles in a gas are spread so far apart that there is plenty of vacant space between them. This space allows them to be pushed closer together.
How does the particle model explain how gases spread to fill their container?
There are no bonds between gas particles and so they are able to move unrestricted by other particles. They travel until they hit the walls of the container.
How does the particle model explain how solids have a fixed shape?
The particles in a solid are strongly bonded to their neighbours, fixing their positions.
What is diffusion?
The movement of particles in a liquid or gas from their region of high concentration to a region of lower concentration, as a result of their random movement. The particles move until they collide with another particle and then change direction. Eventually, the particles will distribute/mix evenly.
Explain viscosity
Viscosity is the measurement of the speed at which a liquid flows. Differences in viscosity can be explained in terms of the attractive forces between the particles in a liquid. Liquids with high viscosity have a stronger/higher attraction between the particles.
Does increasing the temperature of a substance speed up or slow down diffusion? Why?
Speeds it up because the particles move faster.
