Chemistry: Elements/Compounds Lessons

Big Idea

Organic solvents, including TCE, have properties that make them useful for particular applications and necessitate their special handling. 

Essential Question

What are the properties of organic solvents (ex: TCE) that make them useful for particular applications and necessitate their special handling?
 

Learning Cycle

Title

 

Engage

Why are Solvents so Useful? 
DESCRIPTION
Students try different methods of dissolving a stain. They also analyze situations at a coffee plant and ViewMaster factory and choose whether to use solvents. They then propose possible drawbacks to use of these chemicals. 

OBJECTIVES 
Students will: 
*Discover ethanol's usefulness in dissolving a stain. 
*Read accounts of situations at coffee and ViewMaster factories and decide whether to use solvents. 
*Propose possible as-yet-unstated downsides to using new solvents

Explore

How Much TCE is Allowed by Law in Drinking Water? 
DESCRIPTION
EPA standards are in ppb because getting rid of all contaminants is impossible, and present techniques have limits in their detection abilities. 

OBJECTIVES 
*Perform a serial dilution to 5 ppb, the legal limit for TCE 
*Explore detection limits of their own eyes and a spectrophotometer.                                                                 
*Explain why EPA limits are not 0.

WORD Microsfot Word Icon 

Icon for TCE Handouts

Explain

Costs and Benefits of Solvent Use
DESCRIPTION
Students will research general information about TCE- its role as a solvent, its uses, current price and availability, health concerns, environmental concerns, and clean-up techniques.. 

OBJECTIVES 
*Draw a structural model of TCE, and explain the name 
*Analyze the costs and benefits of various clean-up methods *Explain how solvents work, using the word polarity 
*Identify uses, health risks, and alternatives to TCE.

WORD Microsfot Word Icon

Apply

Making decisions about TCE
DESCRIPTION
What would you decide in real situations when TCE is at issue? Is TCE still being used? 

OBJECTIVES 
*Read accounts of TCE use, disposal, health effects, and subsequent clean-up in various sites and analyze the situation, offering decisions.

WORD Microsfot Word Icon

Icon of TCE Handouts