Physical & Chemical Change Lab

Physical & Chemical Change Lab

Name: ______Period: ______Date: ______

Physical & Chemical Changes Lab

Objective: To differentiate between chemical & physical changes

Background:

When a physical change occurs, only the form of the substance changes, not the identity of the substance. Chemical changes, however, result in the formation of new substances with different properties. Some general signs of a chemical change include a change of color or odor, the formation of a precipitate (solid), the formation of a gas, and a change in heat or light. In this lab, you will perform different activities and, based on your observations, determine whether a chemical or physical change has taken place.

Match / Antacid tablet / Vinegar / Water / Sugar
Salt / Test tubes / Hot plate / Aluminum foil / Tongs
Steel wool / Lemon juice / Penny / Effervescing Tablet / Cornstarch
Iodine / Pipettes / Beaker

SAFETY

  • Before lighting the match, tie back long hair and secure loose clothing. After extinguishing the match, thoroughly douse it with water before placing it in the designated waste beaker.
  • Do not ingest any chemicals.
  • Absolutely no goofing off.

PROCEDURE

Perform each of the following activities and carefully observe what happens. After each activity, complete your data table. Dispose of all waste in containers at each station.

  1. Steel Wool: Using the tongs, hold the steel wool over a piece of aluminum foil.Carefully light a match and then light a corner of the steel wool.
  2. Tarnished penny: Add 3-4 drops of lemon juice to the penny and wait about 2 minutes, then wipe off.
  3. Heating sugar: Take a pinch of sugar and place it on the foil. Place the foil on the hot plate and heat for 2-3 minutes. Record your observations.
  4. Cootie Catcher: Closely follow the folding directions to make a cootie catcher.
  5. Antacid tablet with vinegar – Add 3-4 drops of vinegar to the top of an antacid tablet.
  6. Dissolving salt in water – In a test tube, dissolve a small amount of salt in water.
  7. Effervescing tablet – Add about 100 mL of water to the beaker. Drop ½ of an effervescing tablet in the water.
  8. Cornstarch and iodine: Put a small spoonful of cornstarch on the paper plate. Add 3-4 drops of iodine to the cornstarch.
Activity Number / Chemical or Physical Change / Observations/Evidence
Key word:
Key word:
Key word:
Key word:
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Key word:

Directions:

Look at each of the following situations and identify as CHEMICAL or PHYSICAL, then explain why.

  1. A bridge is rusting______

WHY?

  1. Ice cube melting______

WHY?

  1. Mix baking soda and Vinegar______

WHY?

  1. Cooking a hamburger______

WHY?

  1. A pane of glass is shattered______

WHY?

Explain what a chemical & physical change is and give examples of each. Your audience is third graders. Use complete sentences.

______

Using the key words you found while working through the stations, you will now complete the inner part of the cootie catcher. On the two corners behind each of the main four flaps, write the two key words that match that category. Finally, under the flap of each key word, write an example of the word.

For example – behind physical property you could have ductility then under the ductility corner you could write “copper is pulled into a wire”.

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