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Chapter 7 - Coggle Diagram
Chapter 7
change in state
melting
- Melting is the process in which a solid changes into a liquid without a change in temperature.
- When a solid is heated, its particles gain energy. They vibrate faster about their fixed positions. They eventually gain enough energy to overcome the very strong forces of attraction between them. The solid melts and becomes a liquid
- During melting solid particles gain heat energy (energy change)
freezing
- When a liquid is cooled, its particles lose energy and move slower. This causes the particles to be pulled much closer to one another by the forces of attraction between them. The particles are eventually held in fixed positions. The liquid freezes and becomes a solid.
- Freezing is the reverse of melting.
boiling
- Boiling is the process in which a liquid changes into a gas without a change in temperature.
- When a liquid is heated, its particles gain energy. They move faster and further apart from one another. They eventually gain enough energy to overcome the strong forces of attraction between them. The liquid boils and becomes a gas.
condensation
- Condensation is the reverse of boiling.
- When a gas is cooled, its particles lose energy and move slower. This causes the particles to be pulled closer to one another by the forces of attraction between them. The gas condenses and becomes a liquid.
- particles of a substance do not change during a change in state
diffusion
-Particles, which are in constant and random motion, move from a region of higher concentration to a region of lower concentration. This means that the overall or net movement of particles takes place from a region of higher concentiation to a region of lower concentration evenly Spread out
- When we refer to a solution of high or low concentration, it means that there is a large or a small amount of solute particles, respectively, in a volume of solution
- The ink particles move randomly in various directions. The concentration of ink particles throughout the beaker of water eventually becomes uniform or the same due to the overall or net movement of the ink particles.
Diffusion is the net movement of particles from a region of higher concentration to a region of lower concentration
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expansion
- When a substance in the solid state is heated, its particles gain energy and vibrate more vigorously about their fixed positions. The distances between the particles increase. This causes the volume of the substance to increase. As a result, the substance expands.
- Upon cooling, the distances between the particles in a liquid and a gas change in a similar manner as those in a solid. This results in an increase or a decrease in volume of the substance.
- The number and size of particles in a substance do not change during expansion and contraction. Thus, there is conservation of mass.
contraction
- When a substance in the solid state is heated, its particles gain energy and vibrate more vigorously about their fixed positions. The distances between the particles increase. This causes the volume of the substance to increase. As a result, the substance expands.
- Upon heating the distances between the particles in a liquid and a gas change in a similar manner as those in a solid. This results in an increase or a decrease in volume of the substance.
- The number and size of particles in a substance do not change during expansion and contraction. Thus, there is conservation of mass.
Brownian motion
-the random movement of microscopic particles suspended in a liquid or a gas
-all the particles of one pure substance are identical
-it proves that matter can be made up of small, discrete particles which are in constant and random motion