Unit 2 Home Labs - Key

Unit 2 Home Labs - KEY Goals:
 Read Safety
 Perform Changes: Physical or Chemical Lab
 Perform Special Physical Properties of Matter Lab
 Perform Paper Chromatography Lab Turn-in:
1) Changes: Physical or Chemical Lab - Completed Procedure / Observations, questions, and a written description of most important concept that you learned in the discussion section.
2) Special Physical Properties of Matter Lab – Completed Procedure / Observations, questions, and a written description of most important concept that you learned in the discussion section.
3) Paper Chromatography Lab – Completed Procedure / Observations, questions, and a written description of most important concept that you learned in the discussion section.
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Changes: Physical or Chemical - KEY V. Questions:
1.Give examples of where the following properties are important.
Absorbency – foam for packing materials
Hardness – carbide bits to cut steel
Brittleness – Peanut shell
Malleability – Forging steel into materials
Elasticity - Rubberbands
Flexibility - Clothing
2. Why are some substances, like oil and gold, valued more than others?
They are rare and require refining – which costs $.
3. Steel is actually a mixture of iron with a small percentage of carbon. By using different ratios of iron to carbon, different properties are obtained for different steels. What are some different properties that might be valuable for different types of steel?
Hardness, flexibility, density, etc.
VI. Discussion: The most important thing that you learned. | _______________________________________ Special Physical Properties of Matter - KEY V. Questions:
What are some things to look for to decide if a change is chemical?
Color change, produce heat, absorbs heat, evolves fumes, etc.
Aluminum produces a white coating in the presence of air that contains salt-water. Is a physical or chemical change