What are those state of matter changes called? Solid Liquid Gas and Plasma

The process of turning a liquid to a gas BELOW the boiling point. Happens at the surface! = evaporation Gaining energy

The process of turning a liquid to a gas AT the boiling point. Happens throughout substance! = vaporization Gaining energy

The process of turning a liquid to a solid. = freezing Losing energy

The process of turning a gas to a liquid. = condensation Losing energy

The process of turning a solid to a liquid. = melting Gaining energy

The process of turning a solid to a gas. = sublimation Gaining energy

B A Why is the plateau at section “B” much longer than at section “A”?

If you combine what you know about the individual states of matter with what you know about state changes… you can come up with a definition that explains what is going on at the molecular level of a state change. Challenge: Write the molecular definition for each state change.

Molecules which have been rigid gain enough energy to move freely and escape the bonds between them. = sublimation (molecular) Gaining energy

Rapidly moving molecules gain more energy which allows them to escape the bonds between them at the boiling point. = vaporization (molecular) Gaining energy

Rapidly moving molecules gain energy below the boiling point which allows them to escape the bonds between them. = evaporation (molecular) Gaining energy

Molecules which have been rigid gain enough energy to move freely, but are not able to escape the bonds between them. = melting (molecular) Gaining energy

Rapidly moving molecules lose energy and can no longer resist the bonds between them, but are still able to move freely. = condensation (molecular) Losing energy

Molecules which have been moving freely but not able to escape the bonds between them lose energy and vibrate in place. = freezing (molecular) Losing energy

Vaporization Evaporation Melting Sublimation

Condensation Freezing

The “flat lines” or plateaus on the graph show that even though the substance is continuing to be heated there is no change in temperature. If we are reading the graph to the right, the energy is going to the weakening or breaking of bonds. If we are reading the graph to the left, the energy is going to the rebuilding or strengthening of bonds.

Why is the plateau from liquid to gas so much longer than the plateau from solid to liquid? It takes a lot more energy to break or reform bonds than it does to weaken or strengthen them!!!

A phase diagram can be used to identify a substance by its plateaus!!! What key physical properties do the plateaus tell us?!?! Melting pts. and Boiling pts.!!!

Lets say you come across an unknown solid substance… one way to identify it is to apply heat and graph its phase diagram… Phase Diagram…

Freeze Solid Gas Evaporation Condensation Liquid Vaporization Melting Liquid Solid F G Melting Point Boiling Point (Bonds are weakening) (Bonds are Breaking) Label all the different sections with the correct phase change...

A. Sublimation, condensation B. Freezing, condensation C. Evaporation, freezing D. Melting, vaporization

A. Weakening and strengthening B. Breaking and weakening C. Breaking and reforming D. Strengthening and reforming

A. Melting and vaporization points B. Condensation and sublimation points C. Evaporation and vaporization points D. Melting and boiling points

A. It takes more energy to break and reform bonds B. Because the molecules have more kinetic energy C. It occurs because it is at the microscopic level D. Because I said so!

A. Vaporization B. Evaporation C. Melting D. sublimation

A. The energy the molecules have are being used change the bond type. B. It does change it is just to small to read on a thermometer. C. They are using their energy to move freely

A. Condensation B. Vaporization C. Sublimation D. freezing

A. A B. B C. C D. D

A. LiCl B. CaO C. AlCl 3 D. SO 2

A. A B. B C. C D. D E. E

A. Vaporization B. Evaporation C. Melting D. condensation

A. True B. False

A. True B. False

A. Melting B. Condensation C. Sublimation D. Evaporation E. vaporization

A. One happens at the surface and one happens above it’s boiling point B. One loses energy and one gains energy C. One happens above it’s boiling point and one happens above it’s melting point.