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

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: 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 Most of the discussion will be like the last one you wrote Lab 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