Applying Green
Chemistry to
Purification
Honors Chemistry Lab
Pre Lab Guiding
Questions/Simulations
 Part
1: the 12 Principles of Green
Chemistry



Nothing should be left over!
Review Website
Answer Questions
 Part


2: Percent yield
Review Website
Answer Questions
Key Points:
 Some


chemists harvest materials from nature
Separate substances in them
Make new substances from them
 Pure
substances have unique properties that can be
used in distinguishing among them

They consider the benefits and risks of different
options when deciding which is the best chemical
process to use
Relating the Information to This Lab:
 Apply
the differences in chemical reactivity upon
heating for each substance in the mixture

Na2CO3 and NaHCO3
 Evaluate

the efficiency of the process
Financial cost or detriment to the environment
 Percent

Yield
Environmental health
 Minimize


wastes and biproducts
Atom Economy: Ratio of the theoretical yield of desired
product compared to total theoretical yield of all products
D/T * 100%
The lower the atom economy, the less efficient the process
is because more wastes are produced in the process
Procedure Development:


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
How will you determine the relative amounts of
Na2CO3 and NaHCO3 in the mixture?
Use the 12 principles of green chemistry and
stoichiometry
Materials: Refer to lab packet
Procedure guidelines:
 Use
4 to 5 g of mixture
 How many times will you heat-cool-weigh?
 How long will you heat the mixture each time?


How to heat a crucible
Safety Concerns
What Data Will You Collect?
 Data
tables prepared
 Observations
What Will You Calculate?
 Masses
of each component of the mixture
 Percent composition of the mixture
Lab Report Requirements
 ALL

parts of the lab report
Reaction!!!
 Discussion

Information
Focus on the science behind the reaction that
occurred
 Define
terms, use the lab for examples
 Only one paragraph on how this lab relates to
green chemistry

 Lab
Most of the discussion will be like the last one you wrote
is due ___________
Lab Report Review
 In
Class
 Review data from “other students” and
analyze for greenness of the procedure
 Counts as a quiz grade

No lab quiz for this lab