Daily Warm-Up Exercises Day 23 What is the main ingredient in limestone? calcium carbonate What was the purpose of the seawater investigation we did on Day 22? The purpose was to try to find out where the calcium carbonate comes from and how it gets into limestone. What did the liquid in the cup represent? seawater When you blew into the straw, what were you adding to the liquid? carbon dioxide What are marine organisms? plants or animals that live in the ocean Daily Warm-Up Exercises 1 Daily Warm-Up Exercises 1

Testing for Calcium Carbonate (Part 2) Investigation 5 Limestone

Review Limewater Investigation Why did we blow into the limewater? The limewater represented ancient seawater. Blowing into it simulated marine organisms exhaling in an ancient sea. What happened? The water got cloudy and a white powder settled to the bottom of the cup. Daily Warm-Up Exercises 3

What type of materials contain calcite? We have some materials that might be found in the sea. Investigate if any of these materials might contain calcite. Chart your: CaCO3 Observations Material Fizz No Fizz Precipitate 2. 3. 4. 5. 6.

Finish Seawater Investigation Answer the questions at the bottom of the Seawater Investigation worksheet.

Results Which materials fizzed in acid? precipitate (CaCO3) plaster of Paris Baja Mexico sand marble rock shell pieces oyster pieces sea shells How do you think limestone forms? What process might produce a rock that fizzes? Daily Warm-Up Exercises 6

Limestone Formation #1 Some marine organisms have shells made of calcite. When the animals die, the shells settle to the bottom. Layers pile up, and the shells get compacted and cemented together to form limestone.

Limestone Formation #2 Marine organisms exhale CO2 into the seawater. The CO2 reacts with calcium in the water to form calcite powder. The calcite powder settles to the bottom and gets compacted and cemented together to form limestone.

Calcite Limestones fizz in acid because they contain calcite (calcium carbonate). When acid reacts with calcite, carbon dioxide gas is produced. The fizzing is the CO2 being released. Where does the calcite come from? What type of environment?