A special partnership between theGeorgia Department of Education and the

Educational Technology Training Centers in support of the 8th Grade Physical Science

Frameworks.

Module 3:

Food and Cooking

StandardsContentS8P1. Students will examine the scientific view of the nature of matter. e. Distinguish between changes in matter as physical (i.e. physical change) or chemical (development of a gas, formation of precipitate, and change in color). g. Identify and demonstrate the Law of Conservation of Matter.

CharacteristicsS8CS2. Students will use standard safety practices for all classroom laboratory and field investigations. a. Follow correct procedures for use of scientific apparatus. b. Demonstrate appropriate techniques in all laboratory situations. c. Follow correct protocol for identifying and reporting safety problems and violations.  S8CS4. Students will use tools and instruments for observing, measuring, and manipulating equipment and materials in scientific activities utilizing safe laboratory procedures. a. Use appropriate technology to store and retrieve scientific information in topical, alphabetical, numerical, and keyword files, and create simple files. b. Use appropriate tools and units for measuring objects and/or substances. c. Learn and use standard safety practices when conducting scientific investigations.  S8CS6. Students will communicate scientific ideas and activities clearly. c. Organize scientific information in appropriate tables, charts, and graphs, and identify relationships they reveal.  S8CS9. Students will understand the features of the process of scientific inquiry. Students will apply the following to inquiry learning practices: a. Investigations are conducted for different reasons, which include exploring new phenomena, confirming previous results, testing how well a theory predicts, and comparing different theories. b. Scientific investigations usually involve collecting evidence, reasoning, devising hypotheses, and formulating explanations to make sense of collected evidence. e. Accurate record keeping, data sharing, and replication of results are essential for maintaining an investigator’s credibility with other scientists and society. f. Scientists use technology and mathematics to enhance the process of scientific inquiry.

Enduring Understandings:

Energy is neither created nor destroyed but can be transformed.

Energy is involved in chemical and physical changes.   As particles are exposed to increasing levels of energy, their speed of movement increases and they will experience a change of phase.   Essential Question:   Why do onions make you cry, why do lemons taste sour, and why do sliced apples turn brown after they set in a bowl for awhile?

Pre-Assessment: Identify the physical and chemical changes in each event.

Chemical ChangesPhysical Changes

Boiling an Egg

Burning a Candle

Baking Bread

Pre-Assessment: Identify the physical and chemical changes in each event.

Chemical ChangesPhysical Changes

Making Vinegar from Apples

Making Cheese, Yogurt or Buttermilk

PullPull

The baking soda demonstrations can be done using the QX5 digital microscopes or by using a large beaker and a document camera.

Heated slowly, the marshmallow will melt (physical change). Heated quickly to a high enough temperature, the sugar will react with oxygen in the air and burst into flame.

Teacher Demonstration:

Introduce the concept of physical and chemical changes using one of the following demonstrations:

Add water to baking sodaAdd vinegar to baking sodaHeat a marshmallow

Station 1:

Materials:test tube in a tube rack10 mL graduated cylindereyedroppertweezers

Directions:Measure 5 mL of hydrogen peroxide into test tubeMeasure the temperatureUse the tweezers to transfer the potato or liver into the test tubeMeasure the temperatureRecord observations

thermometer3% hydrogen peroxidepieces of liver or potato

Station 2:

Materials:apple slices"Fruit Fresh" or lemon juice

Directions:Compare the treated and untreated apple slicesRecord observations

Station 3:

CAUTION: HOT SURFACE!

Materials:hot plateevaporating dishmargarine

Directions:Place a piece of margarine in the evaporating dishUsing tongs, place the dish on the hot plateRecord observations

Station 4:

Materials:10 mL graduated cylindertest tube in a tube rackgreen food coloringwater

Directions:Measure 5 mL of water in test tubeAdd 10 drops of green food coloringRecord observations

Station 5:

Materials:10 mL graduated cylindertest tube in tube rackgreen food coloringdropper bottle of bleach

Directions:Add 5 mL of water to test tubeAdd 10 drops of green food coloringAdd 10 drops of bleachRecord observations

Station 6:

Materials:walnutsscissors

Directions:Use the scissors to cut the nuts into smaller pieces.Record observations

Station 7:

CAUTION: HOT SURFACE!

Materials:hotplatebeakerwater

Directions:Observe the boiling waterRecord observations

Station 8:

CAUTION: HOT SURFACE!

Materials:hotplatebeaker of boiling water

Directions:Add a dropper of beaten egg white to the beaker of boiling waterRecord observations

egg whiteeye dropper

Station 10:

Materials:beakertwo 25 mL graduated cylinder25 mL milk25 mL vinegar

Directions:Measure 25 mL milkPour milk in beakerAdd 25 mL vinegar to beakerRecord observations

Station 11:

Materials:sugar50 mL graduated cylinderbeakerwater

Directions:Measure 5 g of sugarPour water into beakerDissolve sugar in 50 mL waterRecord observations

Station 12:

Materials:baking sodavinegarbeaker25 mL graduated cylinder

Directions:Measure 5 g of baking sodaAdd to beakerMeasure 15 mL of vinegarAdd to beakerRecord observations

Station 13:

Materials:egg shellvinegarsmall beaker

Directions:Place small chips of egg shell in small beaker of vinegarRecord observations

Assessment:

Use a digital camera to take a picture of each change

Complete the data chart provided

Arrange pictures into two categories: physical changes and chemical changesBeside each picture, explain why the change was physical or chemical