MS-PS1-2

SCUSD NGSS Curriculum Guide ====**MS-PS1-2: Analyze and interpret data on the properties of substances before and after the substances interact to determine if a chemical reaction has occurred. ** [Clarification Statement: Examples of reactions could include burning sugar or steel wool, fat reacting with sodium hydroxide, and mixing zinc with hydrogen chloride.] [//Assessment boundary: Assessment is limited to analysis of the following properties: density, melting point, boiling point, solubility, flammability, and odor.//] ====

Science Background for the Teacher:
Evidence of a chemical reaction includes: color change, Change in state (bubbles or fizzing), temperature change, odor.

Evidence compared to proof. Combining yellow and blue dye created green dye... Not an chemical reaction. Combining Vinegar(clear) to cabbage juice (blue) it turns red..this IS a chemical reaction. color change is not proof of a chemical reaction, it is evidence. The only way to know definitively if there is a chemical reaction is to test the properties of the new substance (density, boiling point, etc).

Key Vocabulary:

 * analyze || interpret || model (as a noun) || melting point ||
 * boiling point || solubility || flammability || odor ||
 * atom || molecule || chemical reaction || physical property ||
 * chemical property || density || evidence ||  ||

Possible Assessments (formative and/or summative):
Analyze an activity and its corresponding data that shows a chemical reaction and one that shows no reaction. Have students mix 2 things, chart observations of changes, and explain why they think a chemical reaction occurred or did not occur.

Key Student Activities:
Burning sugar activity from the textbook (8th grade). Heating salt in a test tube. "Supermarket science"- combine different common liquids and chemicals in ziplock bags and observe changes that they record (attached below)

Key Teacher Demos/Activities:
Add sulfuric acid to a sugar (OUTDOORS!). Make sure not to touch the black snake or inhale the fumes. Or just show a video of this reaction. (Dehydrating sugar)

Combine zinc and hydrochloric acid.

Heat sulfur and iron.

Burn a match.

Common Student Misconceptions :
All bubbles do not denote a chemical change. All color changes are not a chemical change.

Things to Avoid/Correct:
Avoid going into the molecular level unless you are discussing bonds/ formulas.

====Other Resources (text, video, simulations, activities, models, etc..): ====

Show video of "dancing gummy bear"