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Current Event -- Oil Drill Site Explosion

1/26/2018

Many of you are preparing/giving Midterm Examinations. A previous blog post that may be useful is from 01/04/2015 titled Midterm Examinations. This Current Event might be a source of a short-answer or essay question.

The book Chemistry on a Budget contains inexpensive chemistry labs that are useful with easy to obtain materials.

There are two versions of each lab, one with a ten-question conclusion and one with directions for a full lab report. This way the teacher has the option! Each lab is two pages to allow for one two-sided handout.

A 5-Star Customer Review of Chemistry on a Budget at amazon.com states:
“[S]traight forward, to the point, using household chemicals…this is the lab book for you.
I teach high school chemistry and this is exactly what [I] was looking for. Labs included simple household chemicals that could be easily found. Nice format, easy to follow along procedures, and touches on every topic of our chemistry curriculum.”

You can buy this lab book for $23 at amazon.com or lulu.com. It will take 1-2 weeks to get to you -- Order Now. It’s a great resource!

http://www.amazon.com/Chemistry-Budget-Marjorie-R-Heesemann/dp/0578129159/ref=sr_1_1?s=books&ie=UTF8&qid=1389410170&sr=1-1&keywords=chemistry+on+a+budget

http://www.lulu.com/shop/marjorie-r-heesemann/chemistry-on-a-budget/paperback/product-21217600.html

*Some of you have already purchased my lab book – be sure to check out Page 141 !

As reported on January 22, 2018, “Five people are missing after a fiery explosion ripped through an eastern Oklahoma drilling rig on Monday, sending plumes of black smoke into the air and leaving a derrick crumpled on the ground, emergency officials said.

More than 20 employees were at the natural gas well site when the blast was reported around 8:45 a.m., Pittsburg County Sheriff Chris Morris said. Aerial footage showed several fires were still burning by midday on the rig and other equipment; the derrick, a towering metal structure above the well, collapsed onto the ground.

Emergency crews were pulled away after other explosions at the site, where several tanks are also located, Pittsburg County Emergency Management Director Kevin Enloe said during an afternoon news conference.”
http://www.ozarksfirst.com/news/emergency-official-5-missing-after-oklahoma-rig-explosion/932234287

“A person who owns land near the drilling site told KOTV the explosion killed cattle in the area. …

Skinner said a company that specializes in rig fires and other well control problems also responded to the blaze.”
https://www.cbsnews.com/news/pittsburg-county-oklahoma-rig-explosion-live-updates/
This report also includes a brief news report of the incident.

Other blog posts about Combustion reactions include:
01/22/2014       Combustion of a Hydrocarbon
03/05/2014        Heat and Energy
07/13/2014        Chemistry Laboratory Safety
11/25/2014        Predicting Products of a Combustion
                            Reaction (5th Rxn Type)
01/22/2016        Methane Leak in California
02/24/2017        Cleaner Cookstoves

*This Blog contains several entries that would be helpful to your chemistry classroom. Check out the Topic List to help you to find past Blog entries.

Also, Write To Me about your successes, challenges, or questions in the Chemistry Classroom.

Remember, buying a copy of the lab book Chemistry on a Budget can be very useful to your Chemistry classroom with labs and class article ideas.

Have a great weekend!

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Water-based, energy-saving air-conditioner

1/19/2018

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Just a reminder, Midterm Examinations are approaching for some classes – one previous blog post that may be useful is from 01/04/2015 titled Midterm Examinations.

The book Chemistry on a Budget contains inexpensive chemistry labs that are useful with easy to obtain materials.

There are two versions of each lab, one with a ten-question conclusion and one with directions for a full lab report. This way the teacher has the option! Each lab is two pages to allow for one two-sided handout.

A 5-Star Customer Review of Chemistry on a Budget at amazon.com states:
“[S]traight forward, to the point, using household chemicals…this is the lab book for you.
I teach high school chemistry and this is exactly what [I] was looking for. Labs included simple household chemicals that could be easily found. Nice format, easy to follow along procedures, and touches on every topic of our chemistry curriculum.”

You can buy this lab book for $23 at amazon.com or lulu.com. It will take 1-2 weeks to get to you -- Order Now. It’s a great resource!

http://www.amazon.com/Chemistry-Budget-Marjorie-R-Heesemann/dp/0578129159/ref=sr_1_1?s=books&ie=UTF8&qid=1389410170&sr=1-1&keywords=chemistry+on+a+budget

http://www.lulu.com/shop/marjorie-r-heesemann/chemistry-on-a-budget/paperback/product-21217600.html

*Some of you have already purchased my lab book – be sure to check out Page 141 !

“Paul Hawken, the editor of Drawdown, says that air conditioning [AC] contributes a shockingly high amount of atmospheric emissions. The global demand for AC is increasing rapidly thanks to rising economic prosperity in developing countries and higher average temperatures. By 2050, Hawken says hydroflourocarbons, the refrigerants that make air conditioning possible, will account for 19% of all atmospheric emissions. If the world got 21% of its electricity from wind turbines by 2050, the carbon emissions saved would be exceeded by the carbon emissions created to keep us all cool.”
https://cleantechnica.com/2018/01/10/water-based-air-conditioning-slashes-energy-usage-uses-no-refrigerants/

“A team of researchers from the National University of Singapore (NUS) has pioneered a new water-based air-conditioning system that cools air to as low as 18 degrees Celsius without the use of energy-intensive compressors and environmentally harmful chemical refrigerants. This game-changing technology could potentially replace the century-old air-cooling principle that is still being used in our modern-day air-conditioners. Suitable for both indoor and outdoor use, the novel system is portable and it can also be customised for all types of weather conditions.”
https://www.sciencedaily.com/releases/2018/01/180108133239.htm

A brief history:
“Chlorofluorocarbons (CFCs) are nontoxic, nonflammable chemicals containing atoms of carbon, chlorine, and fluorine. They are used in the manufacture of aerosol sprays, blowing agents for foams and packing materials, as solvents, and as refrigerants. …

Refrigerators in the late 1800s and early 1900s used the toxic gases, ammonia (NH3), methyl chloride (CH3Cl), and sulfur dioxide (SO2), as refrigerants. After a series of fatal accidents in the 1920s when methyl chloride leaked out of refrigerators, a search for a less toxic replacement begun as a collaborative effort of three American corporations- Frigidaire, General Motors, and Du Pont. CFCs were first synthesized in 1928 by Thomas Midgley, Jr. of General Motors, as safer chemicals for refrigerators used in large commercial applications. …

Whereas CFCs are safe to use in most applications and are inert in the lower atmosphere, they do undergo significant reaction in the upper atmosphere or stratosphere. In 1974, two University of California chemists, Professor F. Sherwood Rowland and Dr. Mario Molina, showed that the CFCs could be a major source of inorganic chlorine in the stratosphere following their photolytic decomposition by UV radiation. In addition, some of the released chlorine would become active in destroying ozone in the stratosphere. …

Ozone absorbs harmful ultraviolet radiation in the wavelengths between 280 and 320 nm of the UV-B band which can cause biological damage in plants and animals. A loss of stratospheric ozone results in more harmful UV-B radiation reaching the Earth's surface. Chlorine released from CFCs destroys ozone in catalytic reactions where 100,000 molecules of ozone can be destroyed per chlorine atom.

A large springtime depletion of stratospheric ozone was getting worse each following year. This ozone loss was described in 1985 by British researcher Joe Farman and his colleagues. It was called ‘the Antarctic ozone hole’ by others. …The need for controlling the CFCs became urgent.

In 1987, 27 nations signed a global environmental treaty, the Montreal Protocol to Reduce Substances that Deplete the Ozone Layer, that had a provision to reduce 1986 production levels of these compounds by 50% before the year 2000.” https://www.esrl.noaa.gov/gmd/hats/publictn/elkins/cfcs.html

“For one, air conditioning isn’t so much about ‘destroying’ heat as it is about taking it somewhere else — specifically, out of the room. Comfy on the inside, but the reverse of the coin is that the ‘outside’, especially if you live in a big city, gets much warmer very fast. Le Chatelier’s principle on equilibrium tells us that this will make it progressively more difficult for air conditioning units to actually push all that heat outside: it’s more laborious to create a big imbalance (pumping heat from a cold room to a hot outside) than a small one (say, between two bodies at closer temperatures). It’s like pushing water uphill. Which segues us into issue Mk.2:

The harder our ACs have to work, the more energy they need. Ironically, this makes everything hotter, as that energy degrades into heat. It’ll also put a large dent in many a family’s finances, and many people will have to contend with an unenviable choice: go into overdraft, or gamble that nobody’s going to get heatstroke. Zooming back even further, it will put a huge strain on often aging and already-overtaxed power grids — and we definitely don’t want these to pop when everybody’s hugging the AC for dear life.

Lastly, our current systems employ chemical refrigerants such as chlorofluorocarbons and hydrochlorofluorocarbons for cooling, which are quite nasty for the environment. More directly important to you, however, is that these compounds are quite expensive to manufacture and very deadly if leaks occur indoors.

So we need a better alternative. Luckily for us, that’s exactly what one team of researchers from the National University of Singapore (NUS) has been working on, with support from the Building and Construction Authority and National Research Foundation Singapore. The device they came up with could potentially address the limitations of the century-old AC principle in use today.”
https://www.zmescience.com/science/water-based-air-conditioning/

“Led by Associate Professor Ernest Chua from the Department of Mechanical Engineering at NUS Faculty of Engineering, the team's novel air-conditioning system is cost-effective to produce, and it is also more eco-friendly and sustainable. The system consumes about 40 per cent less electricity than current compressor-based air-conditioners used in homes and commercial buildings. This translates into more than 40 per cent reduction in carbon emissions. In addition, it adopts a water-based cooling technology instead of using chemical refrigerants such as chlorofluorocarbon and hydrochlorofluorocarbon for cooling, thus making it safer and more environmentally-friendly.

To add another feather to its eco-friendliness cap, the novel system generates potable drinking water while it cools ambient air.”
https://www.mintselection.com/feed-items/water-based-eco-friendly-and-energy-saving-air-conditioner/

“The water-based air conditioner consumes 40.0% less energy than the currently used compressor-based air-conditioners and helps attain a temperature of 18 degree Celsius.”
https://cmfenews.com/new-eco-friendly-air-conditioners-use-water-cooling-agent/

Past blog posts related to Thermodynamics include:

03/02/2014           Heating and Cooling Curves
03/05/2014           Heat and Energy
03/02/2014           Heating and Cooling Curves
03/04/2015           Calorimetry
01/27/2017           2016 Warmest Year on Record

*This Blog contains several entries that would be helpful to your chemistry classroom. Check out the Topic List to help you to find past Blog entries.

Also, Write To Me about your successes, challenges, or questions in the Chemistry Classroom.

Remember, buying a copy of the lab book Chemistry on a Budget can be very useful to your Chemistry classroom with labs and class article ideas.

Have a great weekend!

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Grading rubrics for lab reports

1/12/2018

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Midterm Examinations are approaching for some classes – one previous blog post that may be useful is from 01/04/2015 titled Midterm Examinations.

The book Chemistry on a Budget contains inexpensive chemistry labs that are useful with easy to obtain materials.

There are two versions of each lab, one with a ten-question conclusion and one with directions for a full lab report. This way the teacher has the option! Each lab is two pages to allow for one two-sided handout.

A 5-Star Customer Review of Chemistry on a Budget at amazon.com states:
“[S]traight forward, to the point, using household chemicals…this is the lab book for you.
I teach high school chemistry and this is exactly what [I] was looking for. Labs included simple household chemicals that could be easily found. Nice format, easy to follow along procedures, and touches on every topic of our chemistry curriculum.”

You can buy this lab book for $23 at amazon.com or lulu.com. It will take 1-2 weeks to get to you -- Order Now. It’s a great resource!

http://www.amazon.com/Chemistry-Budget-Marjorie-R-Heesemann/dp/0578129159/ref=sr_1_1?s=books&ie=UTF8&qid=1389410170&sr=1-1&keywords=chemistry+on+a+budget

http://www.lulu.com/shop/marjorie-r-heesemann/chemistry-on-a-budget/paperback/product-21217600.html

*Some of you have already purchased my lab book – be sure to check out Page 141 !

Lab reports can be a challenge to grade as you want to be consistent with that evaluation. A useful aid for grading those lab reports is to use a Grading Rubric.

“Rubrics are scoring tools that explicitly represent the performance expectations for an assignment or piece of work. A rubric divides the assigned work into component parts and provides clear descriptions of the characteristics of the work associated with each component at varying levels of mastery. Rubrics can be used for a wide array of assignments: papers, projects, oral presentations, artistic performances, group projects, etc. Rubrics can be used as scoring or grading guides, to provide formative feedback to support and guide ongoing learning efforts.”
https://www.rit.edu/academicaffairs/outcomes/rubrics

“Rubrics can be used for any assignment in a course, or for any way in which you ask students to demonstrate what they've learned.”
https://teaching.berkeley.edu/resources/improve/evaluate-course-level-learning/rubrics

“Rubrics help instructors:

Provide students with feedback that is clear, directed and focused on ways to improve learning.
Demystify assignment expectations so students can focus on the work instead of guessing ‘what the teacher wants.’
Adapt your approach to teaching aspects of a course based on thematic gaps in student learning that are easily identified by reviewing rubrics across a class.
Develop consistency in how you evaluate student learning across students and throughout a class.
Reduce time spent on grading; Increase time spent on teaching.

Rubrics help students:

Focus their efforts on completing assignments in line with clearly set expectations.
Self and Peer-reflect on their learning, making informed changes to achieve the desired learning level.”

“Rubrics are typically created as a grid that describes several levels of quality for each aspect of the assignment that the faculty member plans to evaluate.”
https://cirt.gcu.edu/teaching3/tips/rubris

“Analytic rubrics describe work on each criterion separately. Holistic rubrics describe the work by applying all the criteria at the same time and enabling an overall judgment about the quality of the work. The top panel of Figure 1.2 defines analytic and holistic rubrics and lists advantages and disadvantages for each.
For most classroom purposes, analytic rubrics are best. Focusing on the criteria one at a time is better for instruction and better for formative assessment because students can see what aspects of their work need what kind of attention. Focusing on the criteria one at a time is good for any summative assessment (grading) that will also be used to make decisions about the future—for example, decisions about how to follow up on a unit or decisions about how to teach something next year.”
http://www.ascd.org/publications/books/112001/chapters/What-Are-Rubrics-and-Why-Are-They-Important%C2%A2.aspx

Here is an example of a rubric for essays. You may wish to use this guideline when grading essay portions of Tests:
http://wid.ndia.org/about/Documents/WID_EssayRubric.pdf

Many forms presented below use a 4-point system for each part graded, and the various parts would be added up. You can then calculate a percentage of that result (for example 13/15 = 87%) – if desired, that easily becomes an A, B, etc. It also give you, the teacher, feedback about what concepts were not being completed by the majority of the class, what needs to be revisited or clarified, and what concepts/unique parts of that Lab need emphasis in the future.

Here is a general rubric form for science reports that may be useful:
http://www.rubric-maker.com/samples/science_experiment_prim.pdf

Here is another example specific to Laboratory Reports:
http://www.ucdenver.edu/faculty_staff/faculty/center-for-faculty-development/Documents/Tutorials/Rubrics/5_resources/index.htm
You may wish to use this as a teaching tool when discussion with your class your expectations for Laboratory Reports.

Here is a basic (blank) rubric you can edit for the specific assignment:
https://www.teachervision.com/rubric/blank-rubric

This website provides five free rubric making tools:
https://elearningindustry.com/the-5-best-free-rubric-making-tools-for-teachers

I found rubrics useful for grading Lab Reports. My version would list requirements specific to that Lab along with point values for each section.

I used the same basic form and individualized it to each assignment; also, I’d hand that copy out with that lab for easy student reference.

Here is a form of a rubric I designed for my class. I used the same form and simply edited it for each assignment to include specific requirements:

Lab Title:     ____________________________________________

Student:       ____________________________________________

Date Due:     ____________________________________________

Date Received: ________________________________________

Report Section                            Maximum Points                      Points Earned

Title, Purpose, Materials

Procedure

Data (in chart form)

Sample Calculations

Graphs

Discussion & Conclusion

Total Points Earned

What I liked about grading laboratory reports with rubrics is that it took away the question “Why didn’t I do well on my lab report?” It also made it easier to meet with the student about the report and evaluate how to improve their grades in the future. When meeting with the student about the lab, I required that they bring the rubric and the lab being discussed – no lab and rubric, no meeting.

I also would meet with students at their request about the draft report, advise about how to improve it and help with mathematical work. Those students who took advantage of that option always had As or Bs on their reports.

*This Blog contains several entries that would be helpful to your chemistry classroom. Check out the Topic List to help you to find past Blog entries.

Also, Write To Me about your successes, challenges, or questions in the Chemistry Classroom.

Remember, buying a copy of the lab book Chemistry on a Budget can be very useful to your Chemistry classroom with labs and class article ideas.

Have a great weekend!

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Naming elements

1/5/2018

0 Comments

I hope you had a great holiday vacation!

The book Chemistry on a Budget contains inexpensive chemistry labs that are useful with easy to obtain materials.

There are two versions of each lab, one with a ten-question conclusion and one with directions for a full lab report. This way the teacher has the option! Each lab is two pages to allow for one two-sided handout.

A 5-Star Customer Review of Chemistry on a Budget at amazon.com states:
“[S]traight forward, to the point, using household chemicals…this is the lab book for you.
I teach high school chemistry and this is exactly what i was looking for. Labs included simple household chemicals that could be easily found. Nice format, easy to follow along procedures, and touches on every topic of our chemistry curriculum.”

You can buy this lab book for $23 at amazon.com or lulu.com. It will take 1-2 weeks to get to you -- Order Now. It’s a great resource!

http://www.amazon.com/Chemistry-Budget-Marjorie-R-Heesemann/dp/0578129159/ref=sr_1_1?s=books&ie=UTF8&qid=1389410170&sr=1-1&keywords=chemistry+on+a+budget

http://www.lulu.com/shop/marjorie-r-heesemann/chemistry-on-a-budget/paperback/product-21217600.html

*Some of you have already purchased my lab book – be sure to check out Page 141 !

“Since 1947, the International Union of Pure and Applied Chemistry (IUPAC) has had the responsibility for approving elements' names, and deciding the single internationally recognised symbol for each element.
Before this, there were multiple historical occasions of elements being given several names, usually due to simultaneous discovery or uncertainty over a discovery.
The name of element 41 was not agreed for 150 years. It was called columbium in America and niobium in Europe until IUPAC finally decided the official name would be niobium in 1949.“
http://www.bbc.co.uk/science/0/24460393

“The [element] naming process isn't quick. The scientists who discovered them will start things off by proposing a name. But it will be down to the International Union of Pure and Applied Chemistry (IUPAC) to approve it. A special division of the US-based group has to accept the proposal. There is then a public review period of five months before the IUPAC council gets the final approval. Once it's ready, the name is announced in the scientific journal Pure and Applied Chemistry.”
http://www.bbc.com/news/magazine-35225788

“The proposed names for elements 113, 115, 117 and 118 are nihonium, moscovium, tennessine and oganesson respectively, the International Union of Pure and Applied Chemistry (Iupac) has announced…
The groups responsible for the discovery of these new elements each put forward their proposed name and symbol after Iupac confirmed their existence in January 2016. The criteria states an element may be named after a mythological figure or concept, geological place, scientist, elemental property, or mineral.”
https://www.scientificamerican.com/article/4-new-elements-get-names1/

“After years of having to make do with temporary monikers while the elements were officially being added to the periodic table and evaluated by the IUPAC, these new names are much welcomed by scientists. Alas, those calling for names in tribute to great folk of popular culture have gone unheeded; Octarine (the color of magic, according to Terry Pratchett), Ziggium (in tribute to David Bowie’s alter ego Ziggy Stardust) and Severium (in tribute to Alan Rickman and via Severus Snape) will not adorn the updated table.”
http://blogs.discovermagazine.com/crux/2016/06/09/how-the-elements/#.WZ3K0umQzcs

A possible Research Project is to have your students research a specific element and prepare a class presentation or a poster for display in the classroom.

Previous blog posts related to this idea include:
07/06/2014      Decorating Your Classroom
04/01/2015      NOVA video "Hunting the Elements" (2012)
01/07/2016      Four New Elements
06/12/2016      New Elements Named

Some blog posts focus on single elements – you may wish to scan over this blog’s Topic List for ideas.

This page presents a brief history of the naming of the elements, and may provide a useful Homework or Extra Credit assignment:
https://qz.com/585741/the-strange-rules-that-dictate-how-new-elements-get-their-names/

*This Blog contains several entries that would be helpful to your chemistry classroom. Check out the Topic List to help you to find past Blog entries.

Also, Write To Me about your successes, challenges, or questions in the Chemistry Classroom.

Remember, buying a copy of the lab book Chemistry on a Budget can be very useful to your Chemistry classroom with labs and class article ideas.

Happy New Year!

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Current Event -- Oil Drill Site Explosion

Water-based, energy-saving air-conditioner

Grading rubrics for lab reports

Naming elements

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