Name ______

Is it still clay?

Data Analysis for Comparisons

You NEED goggles.

Obtain a small tile of bone dry and bisque from the center table.

Property / Bone Dry / Bisque
Color
Texture
Leaves marks on table when rubbed across it
Drop test (see lab instructions on table)
Ground texture (see lab instructions on table)
Response to water (see lab instructions on table)
Property of your choosing
Property of your choosing

Analysis questions

1) Do we have the same stuff or different stuff after being in the kiln?Why/why not?

2) List the macroscopic evidence you have for your answer.

3) Find out whether clay is an element, compound or mixture and provide your answer in the space below.

4) Read kiln article then draw before & after pictures of the molecules in the boxes below.

Bone dryBisque

Glaze Data Collection

Obtain a set of before and after firing glazed tiles whose numbers match.

Complete the data table below

Property / Before firing / After firing
Color
Texture
Sound when held in one hand & tapped with pencil
Response to drop of water added to surface
Property of your choosing

Analysis questions

5) Do we have the same stuff or different stuff after being in the kiln? Why/why not?

6) List the macroscopic evidence you have for your answer.

Read the article, Chem Talk: Metal Compounds and Color in Art. Taken from Active Chemistry

Use the article to answer the questions on the next page.

Questions for: Chem Talk: Metal Compounds and Color in Art

1a) How is glass made?

b) Do you think making glass is a chemical reaction? Why/why not?

2) List some metal oxides that are used in glazing.

3) Why are uranium salts no longer used in glazing?

4) Why is it a bad idea to use lead in ceramic objects that are used for food?

5) Why did early glass have a green tint to it?

Is it still clay? Lab instructions

Drop test

  1. Stand on the table.
  2. Throw the bone dry tile to the floor.
  3. Record observations in the data table
  4. Repeat with bisque tile.
  5. Select a small piece of each for the next part & place the rest in the appropriate spot on the center table.

Ground texture

  1. Use the mortar pestle to grind PART OF bone dry tile into a “powder”.
  2. Record the texture in the data table.
  3. Take a scoop of the “powder” & place it a small plastic cup and label it “bone dry”.
  4. Throw the rest of the powder in the garbage.
  5. Wipe out the mortar pestle with paper towels. You may need wet paper towels.
  6. Dry the mortar pestle.
  7. Repeat with bisque tile

Response to water

  1. To theplastic cup with bone dry powder add two drops of water.
  2. Stir the contentswith a toothpick to mix the powder and water.
  3. Add a couple more drops & stir.
  4. Keep adding water & stirring until you have a good mixture.
  5. Record your observations in the data table.
  6. Repeat with bisque.

Other properties

For the remaining rows decide on a property, describe it and fill in the appropriate description for bone dry & bisque.