Chemistry 12 March 2012

• Today: Summarizing the process of stoichiometry, with 2 examples

• 1st 10 minutes: Filter your lab product and place on a glass dish in the drying oven

• Please turn in Stoichiometry worksheets and simulation assignment

The basic questions

• We have established that determining the balance of materials in reactions is based on fixed ratios. Knowing this, we can ask…..

• What is the limiting reactant?• How much product can I produce?• How much reactants do I need to produce a

certain amount of product?• How much reactant will I have left over?

The gram - mole issue

• Some molecules are heavier than others

• Chemical equations relate molecules to molecules and moles to moles

• You always have to convert grams to moles to do stoichiometry

Example 1: How much product?

• Plants combine carbon dioxide and water to form glucose.

• How much glucose can a plant produce if it is in a closed chamber with 100 g of water and 100 g of CO2?

Example 2: How much reactants do we need?

• Iron (III) oxide can be used as a pigment to make orange paint.

• How much iron metal do we need to oxidize to produce 100 g of iron (III) oxide powder?

Other matters

• Please use the rest of today to filter and dry your product material - Friday, you can complete the lab handout and turn in for credit

• Friday we will also go over another stoichiometry example, and discuss 3rd quarter assessment projects

Today’s plan --

• Dr. Interlandi’s 4 secret self-centered tips for high school seniors– giving you a leg up on the competition….

Tip 1 - Let people know you exist

• Example A: Call the admissions office, and let them know your situation

• Example B: If there’s a professor who does interesting things, go to their office, and ask how you can get involved

• Example C: Go to recitations and interact with teaching assistants who calculate your grade

Tip 2 - Do things for yourself

• Example A: If a class in the catalogue looks interesting, take it

• Example B: If there’s no class for what you want to learn, make one up

• Example C: Start a small business on the side - it’s free, and shows Chutzpa!

Tip 3 - Don’t take things as they are

• Example A: Unfair grade? if you don’t think your grade is fair, tell the professor

• Example B: If you get charged a late fee or parking ticket, politely contest it

• Example C: If the dorm food stinks, ask for a substitute

Tip 4 - Always look out for #1

• Example A - Your friend needs help, but you’ve got to an exam - go and study, tell your friend to call mom.

• Example B - Take the work study job, but let them know if you need to STUDY. They will always let you (get paid) to do that

• Example C - If your family says they can’t afford it, do it anyway. Take out loans and work summers for your tuition.

Bonus philosophical tip

• Remember what W.E.B. DuBois said:– “The purpose of education is not to make men

carpenters, but to make carpenters men”

– And I elaborate: Use your post high school education to deepen your perspective of the world, so you can appreciate other viewpoints, make more informed decisions and be a more powerful force for good in the world.

– (See it’s not really all about you after all)

Chemistry 16 March 2012

• Today: Completing stoichiometry labs and discussing the Q3 assessment projects

• To start on your own: complete any lab measurements, calculations and questions in the 1st half of class. Check out research assignments on class wiki with extra time.

Q3 assessments

• You have the choice of two different projects for your Q3 assessment

• Both projects are due on March 30th, before we go on spring break

• A: Creative Stoichiometry Project (discuss and see handout)

• B: Chemical nomenclature brochure (see next slide)

Important features of brochure• Sweet layout - it should look professional

• Polyatomic ions - include a page that lists the names, and discusses -ite and -ate endings

• System should show how to name ionic compounds, molecular compounds and acids

• System should explain how to get formula from name

Other ideas…

• Flow charts are useful - import from web (with references) or create your own

• This assignment is easiest if you already have some computer formatting skills!!

• Visit pwgwc.wikispaces.com for an example of how to layout a brochure