Apologia Chemistry: Nuclear Atom

Today, we are working on some POGIL exercises: ChemActivity 1 The Nuclear Atom  (Key) and    ChemActivity 2 Atomic Number and Atomic Mass (key) (Scroll down to locate ChemActivity 2.).   Some of this material is new and some review.  I want to wrap up moles before we tackle electron configurations and flame tests.  I think the packet and a final Stoich review will take the entire class.

Wow.  This exercise was painful.  We completed the first part and skipped right to the mole section in the second part. No, I am NOT sure the kids understand the relationship between amu, atoms, and molar mass.  I think they understand the relationships among atomic number, atomic mass, number of protons and neutrons.  I believe they understand the relationship between charge and numbers of protons and electrons.  Am I certain?  Nope.  Here are pix of my notes from class.

You should keep a blog!

I teach Chemistry, Biology, and occasionally Physical Science to home-school Co-op classes.  A friend asked if I do labs.  He thought it would be impossible for a Co-op to offer high quality lab experiences for high school Chemistry classes.  I showed him my Google Classroom and blog.  The primary reason I keep a blog is to document my labs and activities.  The kids keep lab records, too in their notes.  I encourage families to maintain digital portfolios with loads of photos, test copies, notes, and exercises.   My kids have the records they need when they report to online schools.  You should, too!  Are you concerned about privacy?  Save your posts as drafts instead of publishing online.

Science Kits: Which types are the best values?

Good Will and eBay have eScience, Bob Jones, Apologia, and Labpaq kits as listings frequently.  I like eScience and Labpaq kits.  Some lab kits are better buys than others.  I look at a wide variety of kits; my husband and I teach Chemistry, Biology, and Physics classes.  Last summer I taught Human Biology; this summer we are planning a science camp for elementary-aged children.  So, I can use a wide variety of equipment.

I usually do not bid or buy Physics kits.  These kits usually have styrofoam cups, a glass stir rod, mini compasses, a protractor, etc.  This physics kit has a spring scale, digital scale, and tuning fork along with marbles, bolts, a ruler, straws, etc.  However, too often these kits are priced at $50 or more.  No thank you.  I bid and bought a QSL Physics Kit from Good Will two years ago.  I paid $30 with shipping.  Good Will and eBay offer QSL Chemistry, Biology, and Physics kits occasionally.  My price limit is still $35 with shipping.  But the QSL kits are uniformly excellent kits.

The Labpaq kits can be good deals.  This listing is a good example; the kit has a thermometer, digital scale, dissection kit, plastic labware, test tubes, test tube brush, rack, and test tube holder.  This Chem Kit is another good choice; the lab kit has a digital scale, thermometer, multi-meter, sterno, and a molecular modeling kit.  I always discount the chemicals.  Who knows how hold they are?

BTW, the QSL kits are usually designed for high school aged science students.  The eScience and Labpaq kits are designed for college students.  More and more of the nonmajor or introductory science classes are available online, especially through community colleges.  Some students manage to pass the class without doing any of the labs or experiments in the kits.  That is why there are a variety of kits available online, seemingly unused.  These lab kits can be great deals.  I promise to keep you posted.

Science Kit Again

Good Will has an eScience Kit listing that is a decent deal.  The kit has a plastic cylinder, several beakers, a glass thermometer, pipettes, and a few test tubes.  I cannot tell if the safety box has goggles or not.  The shipping weights are accurate.  Sometimes Good Will stores inflate the shipping weight increasing the shipping costs dramatically.  If you are looking for basic science equipment, this kit is priced fairly.  Don’t over bid.  Another kit will be available soon.

Apologia Chemistry: Solubility and Module 11

Today the Chem class redid the Solubility Rules Lab.  I was concerned about cross contamination.  I do teach before, during, and after labs.  For example, we reviewed solubility before resuming lab.  I also asked the kids to identify the types of chemical reactions are involved in precipitate reactions. (Double replacement reactions.)  Before lab, I asked them to identify the solubility rules they already understood.  For example, nitrate compounds are soluble.  Period.  Sodium and potassium compounds are soluble.  Period.  Most silver and lead compounds are insoluble---EXCEPT silver nitrate, silver acetate, lead nitrate, and lead acetate.

During lab, I usually just prompt them and answer questions. For example, the silver nitrate and lithium chloride did not produce a precipitate.  I had the kids add powdered lithium chloride to the silver nitrate to observe the precipitate.   After lab, we summarized their findings.  What are the Solubility Rules?  I make a point of emphasizing that the rules are based on lab observations--just like their lab observations.

After lab the class did reaction predictions for these precipitate reactions--double replacement reactions.  I reviewed the symbols for precipitate reactions.  We did one more set of reaction predictions and identified the solid precipitates.  I also went over the solubility rules lab rubric.

Solubility Rules Lab

Title: Solubility Rules Lab Report

Background:  What does solubility mean?  What is a precipitate? Define soluble and insoluble.  Use the Apologia Chemistry textbook.

Materials: List all of the materials, such as disposable transfer pipettes or wood stir sticks.  The students may summarize the reactants. For example, over one dozen different soluble compounds may be included in the materials instead of listing each compound, such as sodium phosphate solution.

Procedures: The procedures are summarized.  The various reactants, such as barium chloride and potassium sulfate are combined in reaction plates.  The student observes each reaction to note precipitates.

Data Chart:  The data tables my be hand-drawn or electronic versions.

Reaction: Predict, write, and balance one of the precipitate reactions observed during lab.  

Discussion: Identify sources of error.

Citation or Attribution: Use MLA formating to cite the textbook.

Science Kits Again

Here  is another eScience kit online.  While it has 0.01 shipping, the price is $30.  Look at the contents: food wrap, measuring spoons, a few test tubes, pipettes, glass rod, safety glasses,  and plastic beakers.  In the clear bags are miscellaneous items for specific labs: beans, rubber bands, paper clips, tape, etc. (Here is another eScience kit at Good Will.  Look at the photos of the contents.  There is an image of typical items in the small plastic bags.  BTW this kit is $15; however, look at the shipping!  Ouch!).  Note I am discounting the chemicals.  How old are they?  Are these chemicals I use in my labs?  Who knows?  Yes, I am tempted by eScience lab kits, too.  I’m giving this one a hard pass.  I have plenty of test tubes, plastic beakers, and safety glasses.  Keep your eye out for a Labpaq or eScience kit with a digital scale or mortar and pestle instead.

Apologia Chemistry: Metal Reactivity and Solubility Lab

The kids are working through the two labs: metal reactivity and solubility lab.  The class completed the metal reactivity and did several additional labs to determine which metals are more reactive and can displace other metals.  Yes, I could have given them the notes.  Instead, the kids combine the metals and determine which metals are more reactive by adding, say, zinc to magnesium sulfate and magnesium to zinc sulfate.  The metal reactivity series is based on observations.  The kids did additional reactions to confirm the metal reactivity series: zinc and magnesium sulfate, magnesium and zinc sulfate, iron and zinc sulfate, zinc and iron chloride, aluminum and zinc sulfate, etc.  Initially, the kids observed the magnesium and zinc are very reactive; the aluminum and iron appeared less reactive.  Aluminum is quite reactive.  It appears to react more slowly.  So, we put 0.4 g of aluminum with 0.2 M copper chloride solution again.  After a bit of discussion, we performed several reactions to see which metals aluminum displaces.  We hammered home the idea that single replacement reactions are based on a metal’s reactivity.


The kids are still working on the solubility rules lab.  Again, I'm having them make observations and draw conclusions from their observations.  I give heavy hints.  For example, the reactants in the lab are all soluble. Another hint is to react silver nitrate and lead nitrate with as many compounds as possible.  We established that nitrate compounds are soluble.  We also discussed the meaning of soluble, insoluble, and precipitate.  I had assumed these definitions would be obvious.  They are NOT.  Here are some pix.

Apologia Science: CBL2

Good Will online has a CBL 2 listing just added. (This is a similar listing on eBay for $30.)  These devices require a TI 83/84 graphing calculator.  The CBL collects the data from sensors or probes and sends the data to the graphing calculator, usually to the STAT lists.  This listing has a thermometer, light probe, and voltage sensor.  So, the sensors alone are useful even if the CBL does not work.  Often, the owners are intimidated by the devices and they remain unused.  Here is a lab manual.  Here is a ‘quick start’ manual.

These devices are NOT hard to use.  There is a link cable which connects the CBL to the TI 83/84 calculator.  Follow these instructions.  Be sure to use the cable link to connect the CBL2 to the Ti 83/84.  You need a TI 83 PLUS or a TI 84 calculator.  The TI 83 plus has apps and can accommodate the Data Mate app.

Yes, I know I push technology for home-schoolers.  Really, I push cost-effective technology to home-schoolers.  The CBLs are good examples of affordable technology.

I went down to the basement classroom to trouble shoot the CBL 2.  (I just bought one from Good Will about two weeks ago.)  Here are excellent instructions to quick-start collecting data on the CBL2 with a graphing calculator.  I took photos.  I will talk to my kids and see if we can set up an afternoon to do some videos.

                                 My set is identical to the current CBL2 listing on Good Will.

                       I used the TI 84 to test the CBL.  You need a TI 83 plus with the Data Mate app.

                                            Here are the contents with the CBL 2 box.

  The probes included with theCBL2 connect to the TI 84 with Easy Data—preloaded on TI 84 with Easylink.

                         This is how the TI 83 calculator connects on a cradle with the CBL2.

                                  Hi    The probe is inserted into the lowest channel available.

                                 The cable link connects between the CBL2 and the Calc.

     You need a TI 83 plus and must download the DataMate app from the web with the USB connector shown on the right. Here is a link to the TI USB connecting cable for TI 83 calcs.

  The TI 84 had Data Mate preloaded.  I followed the directions to collect temperature data from the Quick Start guide from Mighty Grammarian.

                        See?  The data collected in stored in L1 (trials) and L2 (temperature data)

Apologia Chemistry: Three Labs

The class nearly completed all three labs.   My goal is to complete a minimum of 25 labs.  Next week, we will finish the Solubility Rules lab and debrief all three labs.  Our digital scales are not sensitive enough to determine the difference between the mass of aluminum before and after for the Limiting Reactant lab.  I will review limiting reactants with the kids and predict the theoretical yields together next week.  The second lab was the metal reactivity lab.  The idea is to observe the manner several metals react with copper II chloride solutions.  The difference is distinct.  The only issue was the mossy zinc turns black quickly.  Zinc is more reactive than iron nails.  The kids did not observe the immediate change and thought iron was more reactive than zinc.  The kids are completing the solubility rules lab.  Next time, I need to review the purpose of each lab, discuss the results, and write equations.  We did all of that today.  The problem is the kids just forget.  Below are photos.  I like to include pix because they can be used for the children's digital portfolios.