I will be discussing the chemistry of this article in class on Monday. You might find it interesting…

http://www.straight.com/article-599346/vancouver/mcdonalds-stops-use-ammonium-hydroxide-pink-slime-hamburgers

Here is a check list to help you prepare for the first quiz on Monday:

1. Be able to state the difference between a hypothesis and a theory and a law.

2. Be able to determine if a change is a physical change or a chemical change (hint: chemical changes involve the making and/or breaking of chemical bonds).

3. Know the following metric prefices: Giga, Mega, Kilo, milli, micro, nano, pico (and you should also know centi- for centimeters).

4. Be able to do density problems. There is a drill sheet on density in the review section of the handouts.

5. Review the rules about significant figures but I will not be taking points off for errors with sig. figs. in this first quiz.

6. Be able to describe electrons, protons and neutrons (charge, location, relative mass) and also be able to describe the three main types of radioactive decay products (alpha particles, beta particles and gamma rays)

7. Review isotopic notation. Pay special attention to the equation 2.2 on page 45 and Example 2-3.

8. Be able to convert grams to moles and moles to grams.

9. Be able to determine how many particles are present given the mass of a compound.

10. Be able to calculate percent by mass of an element in a compound e.g. what percentage by mass is oxygen in water.

Here is a photo taken in Duluth, MN. This is an area full of iron ores – so much so that the land is the color of rust.

You can see evidence of iron by the color of the river and rocks.

Here are the rusty squirrels I mentioned in class. The squirrels have figured out how to blend in with their lovely coats that are a perfect match for iron oxide.

Rusty Squirrels Blend in with Iron Rich Terraine

Taconite is the most common ore in this area.

Because of the holiday Chemistry 201 met only once and spent a fair amount of that first class taking a test. Why? Because in order to be successful in Chemistry 201 it is critical to have a good foundation in Basic Chemistry – names of the elements, basic structure of matter, simple chemical equations, nomenclature of inorganic compounds, the metric system and it is also critical to have a good foundation is basic algebra – rearrange equations of solve for an unknown, carry out conversions, use proportional reasoning. Any student who is not very comfortable with these skills should immediately seek out support and hit the books! (and the Internet – there are so many useful videos, worksheets, explanations)

On Monday we will have our first lab so be sure to download and print it! We’ll be analyzing an unknown white powder – one of several common household white powders: sugar, baking soda, etc.

Having a laboratory notebook is very, very important! Please bring it to every class.

All grades for both Chemistry 201 and Chemistry 203 are posted in Blackboard and have been submitted in PeopleSoft. I will be on campus on Wednesday afternoon if you wish to pick up your lab books. Otherwise I’ll hold on to them until June. Please stop by and collect them. Have a wonderful holiday.

Please take a look.

Dear Students,

It is Friday late afternoon and I am still grading lab reports and lab notebooks. It takes time and I ask for your patience. I will keep you posted and let you know when the grades are posted to Blackboard. This will not happen before Monday.

Here is a link to some very good practice problems with answers on the topic of solution concentrations:

http://www.chemteam.info/Solutions/Molality-from-density-and-percent.html

Also I’ve created two handouts which summarize the steps in these conversions:

1. Conversion from molarity to molality

2. Conversion from molality to molarity

Since both classes have exams this week I’ll be available for questions and problem solving practice as follows:

9:00 – 11:00 Monday – focus on Chem 201

11:00 – 12:30 Monday – focus on Chem 203

5:00 – 6:00 Monday – focus on Chem 203

I’ve posted a fourth practice exam under student resources/exams on my website that covers solution concentrations and colligative properties. There is also a key to this exam. Happy studying!

Solutions Quiz Key

1. Review section 4.2 Concentration Units: ppb, ppm, Molarity.

2. Review section 4.3 Dilutions: M1V1=M2V2

3. Review section 4.4 Electrolytes vs. Non-electrolytes

4. Study Figure 10.2 regarding sizes of ions.

5. Be able to put compounds and molecules in order of increasing intermolecular interactions: ion-ion, ion-dipole, H-bonds, dipole-dipole, dipole-induced dipole, dispersion

6. Related intermolecular forces to physical properties such as mp and bp.

7. Identify all the regions of the phase diagram.

8. Know more ways of expressing solution concentration: molality, percent by mass.

9. Be able to interconvert concentration units.

10. Carry out calucations for all colligative properties: vapor pressure lowering, boiling point elevation, freezing point depression, and osmotic pressure.

11. Use the van’t hoff factor correctly.

Solutions problems and collegative properties problems take lots of practice. I will be in my office tomorrow at 9:00 ready to solve problems for whomever arrives!

Determination of Molar Mass by Freezing Point Depression is now available on my website.

Exam Two

Chapter Six

All types of problems with PV=nRT and P₁V₁/T₁=P₂V₂/T₂

Problems about gas density and the relationship to molar mass.

Graham’s Law of effusion (relationship with rate of effusion and molar mass)

The general conditions required for ideal gas behavior.

Description of common gases (as listed on worksheet)

Chapter Seven

Frequency/Wavelength conversions

Identification of areas of the Electromagnetic Spectrum

Who’s who in atomic theory

Relationship between energy and wavelength/frequency

Three main experiments: Photoelectric Effect, Blackbody Radiation and Emission/Absorption Spectra

Quantum numbers and relationship to properties of orbitals (size, shape, orientation in space)

Aufbau principle (1s²2s²…)

Chapter Eight and Nine

Lewis dot structures

Periodic Properties: size and ionization energy

VSEPR Theory

Formal Charge

Shape and polarity of molecules

A special thanks to those students who stayed late yesterday to put in some extra time working on chemistry concepts. This opportunity will be repeated November 30th.