Presentation on theme: "Earth Materials Investigation 3 Calcite Quest Part 2 – Looking for More evidence Day 2."— Presentation transcript:
Earth Materials Investigation 3 Calcite Quest Part 2 – Looking for More evidence Day 2
For the Teacher – Getting Ready Student Materials 1 FOSS tray from previous lesson 2 hand lenses
For the Teacher – Getting Ready Class Materials Response Sheet – Calcite Quest Assessment Chart
What We Will Learn Crystal patterns can help us identify certain minerals. The rocks that contain calcite.
Science Vocabulary Signs or facts on which a conclusion can be based are called evidence. The continuous, tiny bubbles in the form of a string are evidence that calcite is present.
Part 2 Review Why did we pour the liquid in the evaporating dishes and let them sit for several days? Yes, we are looking for evidence of calcite in the four rocks.
Looking for More Evidence Getters get your group’s tray and CAREFULLY carry it to your group. Get hand lenses for your group. Observe the dishes carefully. Do not touch any deposits you find in them.
Observations Draw your observations in your Earth Materials Notebook. Put a check next to the rocks that you are sure contain calcite.
Sharing Reporters share your group’s findings. You should have found white, needlelike crystals in the dishes that contained the liquid from the limestone (a lot) and the marble (some). The dishes from the basalt and the sandstone may contain a thick film of clear to amber material (like the residue you found in the vinegar-only evaporating dish.)
Discussion What evidence do you have that some of the rocks contain calcite? Limestone fizzed actively and left a lot of white crystals Marble may or may not have fizzed, but it did leave some white crystals Sandstone may have had a few bubbles, but no white residue.
Discussion Can you tell which rock has the most calcite? Limestone fizzed a lot and left a lot of white crystals; therefore, it has more calcite.
Discussion Where did the calcite in the dish come from? It dissolved out of the limestone and marble through the action of the vinegar. How long did it take for the calcite to dissolve? Overnight.
Discussion Would limestone and marble be affected by acid rain? Would these rocks erode faster or slower if the rainwater did not contain acid? They would erode slower.
Discussion One of the events that takes place on Earth constantly is the chemical weathering of rocks. The amount of acid in the water affects how long it takes for minerals to dissolve out of rocks.
Clean Up Collectors return the trays and hand lenses please.
Review Geologists use acid, like vinegar, to detect calcite in rocks. They place just few drops on a rock and watch to see if it fizzes. If it fizzes, then they know calcite is present. This information can help them identify the rock.
Content Inquiry Why did we have to do two tests before we could decide which
What We Learned Sometimes more than one test is needed to provide conclusive evidence. Evaporation is a technique used to separate liquid from solid parts of a mixture or solution.
Literature Connection The Two Boys: An Aborigine Story from Australia