Overall Expectations

• demonstrate an understanding of the properties and uses of fluids.

Specific Expectations

• explain the difference between solids, liquids, and gases in terms of density, using the particle theory of matter
• explain the difference between liquids and gases in terms of their compressibility
• explain in qualitative terms the relationship between pressure, volume, and temperature when a liquid (e.g.,
  water) or a gas (e.g., air) is compressed or heated
• explain how forces are transferred in all directions in fluids (Pascal’s law)

Materials

a large open space, eg gym, school yard, cleared space in classroom

Important Terminology

gas, liquid, solid, particle, heat, volume, pressure, temperature, condensation, evaporation, freezing, thawing, sublimation,

Background Knowledge

• basic postulates of particle theory of matter
• How heat affects the motions of particles
• How heat affects the volume of solids
• conduction, convection, radiation

Hook

Due to a lab accident, your science teacher and your drama teacher have switched bodies, so, until your science teacher can find a cure, we are going to do an interpretive dance about the particle theory of matter.

Lesson Sequence

Find or create a large open space.
Explain to the students that they shall be playing the part of particles of matter. Review the basic postulates of the particle theory of matter, and Newtons laws of motion. Remind the students that for safety, all collisions should be interpretive, and not real. They have a force field that will not let another particle get closer than a foot. Their speed should be a normal walk for hot, a slow walk for room temperature, and baby steps for cold.

Starting as a gas, they have to walk around the room in a straight line, and can only change direction when they hit something. Let this go for about 30s, then ask the students what they observed regarding how much of the room they visited, how easy it was to move, how close they were to other particles, and how much space they had, and how often they "hit" the walls of the room. Remind them that when they "hit" another particle, they can transfer energy (heat), and that they number of times they hit is the temperature.

The teacher should take a walk through the gas, and ask the students how easy it is for the teacher to move through the gas, how often the object contacted a particle of gas. Ask them if the teacher is "hit" on all sides equally.

Using your teacher powers, create an invisible wall and compress the gas for 30s and repeat the questions. Point out that both pressure and temperature are dependent on the number of hits, compare these with the uncompressed state.
Pick one corner to be "down". Using your teacher powers, cool the room. Ask the students how often they hit the invisible wall compared to when they were hot. Explain that there is less pressure on the wall now so it will start to fall to the bottom of the room.

Keep cooling until the gas liquefies and flows to the bottom of the room. Remind them that as a fluid, there's still enough room (elbow distance) between them so they can still move around, but are attracted to each other so they can't go beyond the "surface". Re-ask the questions.

Try to compress the fluid, ask the students to compare how easy it is to compared to when they were a gas.

The teacher can then move through the fluid, showing how liquid flows around objects. The teacher should ask the same questions as when he moved thought the gas.

The teacher should now use his powers to slowly freeze the liquid by having the student put their elbows down, right hand on the shoulder of the student in front of them and their left hand on the shoulder of the students to their left. Ask the students to compare the volume they occupied as a warm fluid and a cold one. Repeat the demonstration of compressing the solid and moving through it and re-ask the questions.

Culmination

Review what we've learned on an overhead.

Break the class into heterogeneous groups and assign each one of the following questions and have them create anchor charts to answer them.

• What is the relationship between temperature, pressure, and volume.
• Explain compressibility by the particle theory of matter.
• Show the different properties of solids, liquids and gasses.
• Explain density using the particle theory of matter.
• Explain Pascal's Law using the particle theory of matter.

Key Questions

How much of the room they visited as particles when they were solid liquid and gas. How easy it was to move in these states. How close they were to other particles? How much space they had? How often they "hit" the walls of the room? How compressible are gasses, liquids and solids? How are volume, temperature and pressure related to the particle theory of matter?

Assessment

Use an anecdotal assessment of the children during the exercise to see if they can stay in character.
Use the anchor charts they create to assess their understanding of the particle theory of matter. This is a formative assessment.

Enrichment

Since this is mostly groupwork and whole class activities, there is little room for enrichment

Remediation

As a mostly kinisthetic exercise, no remediation should be needed. The assessment is done on groupwork, so the stronger children in the group will help the weaker.

References

Bubbles in the hot tub : a guide to getting in and out of hot water : an integrated unit for Grade 7/8 / written by Derek Totten ... [et al.] ; Kyn Barker (project lead).
Publisher [Ontario : s.n. ; Waterloo, Ont. : distributed by Graphics Visual Solutions, University of Waterloo], 2001.

Overall Expectations

investigate the properties of fluids

Specific Expectations

• follow established safety practices for using apparatus, tools, and materials (e.g., use syringes and tubing for the purposes for which they were designed)
• investigate and compare the density of a variety of liquids
• investigate and compare the densities of a variety of liquids
• use appropriate science and technology vocabulary, including viscosity, density, particle theory of matter, hydraulic, and pneumatic, in oral and written communication
• use a variety of forms (e.g., oral, written, graphic, multimedia) to communicate with different audiences and for a variety of purposes
• determine the buoyancy of an object, given its density, in a variety of fluids

Materials

Graduated cylinders, balance scales, stirring rods, hydrometers (from previous lesson), water, high fructose corn syrup, sliced fruit (various types), ice water bath.

Important Terminology

mass, volume, density, concentration

Background Knowledge

How to use the INSITE method to design and carry out an experiment.

Hook

We have just recieved the following e-mail from the Whiz Bang Drinks marketing department.
Our company is developing a new beverage. We believe that it would be a big hit if we could suspend pieces of fruit in the drink. We would like to know if this is possible, and if so, how much sugar is required to do this. Please respond ASAP, etc.

Lesson Sequence

The class will be divided into groups and each group will be assigned a fruit. Each group will need to design and carry out an investigation to determine if it is possible to suspend pieces of the fruit in a sugar solution, and if so, quantify the density of the liquid required to suspend different types of fruit, and the percentage of sugar required. As an extension, they should also determine if temperature makes a difference.

Key Questions

Is it possible to create a liquid that will have the same density as a piece of fruit. How do you determine the density of a fluid. How do you create a fluid with a specific density. Does temperature make a difference.

Assessment

The INSITE logbooks will be collected, as well as the e-mail report to Whiz Bang Drinks. They will be evaluated using the attached checklist.

Enrichment

As a group activity, there is little scope for enrichment

Remediation

Weaker students will be supported by stronger students in their group.