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Crush the Can! Youtube:

About In this experiment, we will be looking at what happens when there is a sudden change in air pressure inside an aluminum can.

Materials  An empty aluminum soft drink can  Water  Tongs  Hot plate  Bowl of ice water

Procedure 1. Fill a bowl with cold or ice water. 2. Put about 1 tablespoon (15 mL) of water into an empty soft drink can. 3. Heat the can on the hot plate to bowl the water. 4. When the water boils, a cloud of water vapor will escape from the opening in the can. Wait 30 s. 5. Using tongs, grasp the can quickly and invert it and dip it into the water in the pan.

Tips for Working with Hot Plates  1. When heating material in a bath, make sure the glassware’s heat resistant. Inspect for cracks. Never place a glass flask, soft glass, or jars directly on a hot plate, and make sure the surface of the hot plate is larger than the object being heated.  2. When you are bringing liquids to a boil, adding boiling stones will help facilitate the process.  3. Be careful when condensing the material in a vessel until it’s completely dry. If there is too little moisture and the vessel remains exposed to heat, it will eventually crack.  4. For liquids, including water, it’s a good idea to use either the medium or medium high setting. Low boiling liquids should not be heated at the high setting, which can produce surface temperatures as high as 540 C (1004 F).

 5. It’s advisable not to heat a metal pan on a hot plate, which can damage the hot plate and maybe even pose a shock risk.  6. When removing objects from a hot plate, use tongs or rubber coated, heat resistant gripping devices. The same holds when true when pouring hot liquids.  7. Do not store volatile or flammable materials in the vicinity of a hot plate.  8. Limit the use of older hot plates for flammable materials.  9. Check for corrosion of thermostats, which can create a spark hazard.  10. Perhaps the most important thing of all is to remember to turn the hot plate off. Hot plates that have been left on are the source of most hot plate related injuries.

Task Complete the “crush the can” experiment/activity. After the lesson: In your own words, describe how the particle theory can be used to explain why the can collapsed when you inverted it into cold water. ALTERNATIVE: “Molecules in Motion” Activity

Physical Properties and Particle Theory of Matter Sections 5.1 and 5.2

Physical Properties of Matter Boiling Point: Temperature at which a liquid changes to gas EX. The boiling point for water is 100 degrees Celcius Melting Point: Temperature at which a solid changes to liquid EX. The melting point of water is 0 degrees Celcius Freezing Point: Temperature at which liquid changes to solid; melting point and freezing point are the same temperature for a substance EX. The freezing point of water is 0 degrees Celcius

Particle Theory of Matter Particle theory helps explain the behavior of materials and helps us visualize what is happening on a very small scale inside those materials  1. All matter is made up of tiny particles.  2. All particles of one substance are the same. Different substances are made up of different particles.  3. The particles are always moving.  4. The more energy the particles have, the faster they move.  5. Particles attract each other. Molecules in MotionMolecules in Motion (Multimedia)

5. Particles attract each other. 2. All particles of one substance are the same. Different substances are made up of different particles. 3. The particles are always moving. 4. The more energy the particles have, the faster they move. 1. All matter is made up of tiny particles. Water molecules are made of different atoms than carbon dioxide molecules Motion lines

 This model can be used to explain: 1. The properties of matter. 2. What happens during physical changes such as melting, boiling, and evaporating.

Pure Substances  Made up of only one type of particles  Any element from the Periodic Table  Any compound (like distilled water, carbon dioxide)

Mixtures  Made up 2 or more types of particles  Mechanical mixture – you are able to see the different particles (pizza, oil and vinegar, cereal)  Solution – a mixture where you can’t see the different particles (apple juice, air in this room)

Alloys  Special mixtures of metals.  Bronze – tin and copper  Brass – zinc and copper  14 karat yellow gold – gold, silver, copper, zinc  Solder (pronounced “Sodder”) – lead and tin

Homework 9 Applied: Complete page two of handout 9 Academic: Read pg Questions 2-8 on pg. 178