Chemistry
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April 2019
Philatelic Table of Elements
What would a periodic table made of postage stamps look like? Well, Larry French from St Lawrence University, Canton, New York has taken on this challenge to produce this Philatelic Table of Elements. It was first presented at the spring 2016 American Chemical Society Meeting to mark the International Year of the Periodic Table (IYPT 2019).
Category: Feature Chemistry News and updates Series -
May 2018
Gasoline and diesel fuel: Carbon pricing and heating values
Shortly after New Year’s Day 2017 a radio news item noted that the Province of Ontario’s newly introduced cap and
Category: Feature Chemistry News and updates -
March 2018
Part 3. Building a nanoparticle
In the previous parts of this series, we presented an overview of what nanoparticles are and what they can do. We emphasized the importance of surface atoms as the only ones that can facilitate catalytic reactions.
Category: Feature Chemistry News and updates -
February 2018
Part 2. Estimating the amazing surface areas of the incredibly tiny
In Part 1 of this series we described nanoparticles, what they are, how they are made and how they compare to other forms of metal. We also described how metal surfaces serve as catalysts facilitating reactions such as the hydrogenation of an alkene.
Category: Feature Chemistry News and updates -
December 2017 - January 2018
Part 1: Function and importance of nanoparticles in catalysis
As a science teacher, if you were asked for an example of a catalyst, your car’s catalytic converter may come to mind. Most informed citizens would do the same. What may come as a surprise is that catalytic converters have dramatically changed in the past decade and now use only a small fraction of the precious metals that older models used.
Category: Feature Chemistry News and updates -
November 2017
Quantum dots: Harnessing the nanoscopic rainbow
I co-instruct and coordinate an undergraduate materials and nanoscience (MNS) lab at the University of Waterloo. One experiment in 2nd year consistently stands out as my students’ favourite, and it involves the synthesis and characterization of “capped” cadmium selenide (CdSe) “quantum dots” (QDs).
Category: Feature Chemistry News and updates From our readers Covers -
November 2017
Active ingredient content in tablet (a follow up)
In the December 2016/January 2017 issue of Chem 13 News, I explored the regulation of active ingredient content in pharmaceutical tablets. Recently, purchasing a bottle of Jamieson 400 IU1 (10 g) Vitamin D tablets, I was surprised to see “Improved Smaller Tablets” boldly printed on the label in a blue rosette.1 Why make the small tablets even smaller?
Category: Feature Chemistry News and updates -
October 2017
Who knew?
'Black tongue and Pepto-Bismol” ... quite a little scare. Soon after waking from a night’s sleep, I clear my throat and spit into the bathroom sink...
Category: Chemistry News and updates Pedagogy, opinion and advice Article -
May 2017
Photochromic dyes for plastic lenses: Part 2
In part 1 published in the April 2017 issue, the molecular structures of the photochromic dyes used in eyeglass lenses were discussed. In part 2, the engineering and chemical design of the lenses will be highlighted. The student questions will focus on kinetics and experimental design.
Category: Feature Chemistry -
April 2017
Photochromic dyes for plastic lenses: Part 1
The Merriam-Webster dictionary defines photochromic(1) as: “capable of changing color on exposure to radiant energy (as light), e.g., photochromic glass”. Photochromic eyeglass lenses were introduced in 1966, and photochromic plastic lenses....
Category: Chemistry News and updates -
April 2017
Borax advisory update Health Canada
Health Canada issued an advisory this past summer, suggesting that exposure to boron substances be reduced as much as possible from all sources.
Category: Chemistry News and updates -
April 2017
Starch in place of borax
One can use starch instead of borax to make gak/goo/slime. We published making gak/goo/slime using a saturated borax solution in the October 2016 issue of Chem 13 News.
Category: Activities Outreach Chemistry News and updates -
March 2017
Sources of helium – Some uplifting news
When students are introduced to the periodic table, generally they already recognize a few elements. Even the least scientifically inclined students will have a few names pique their attention.
Category: Feature Chemistry News and updates -
February 2017
What on Earth are Tholins?
In answer to the title question, tholins aren’t on Earth! Well, not naturally on Earth, but they are important elsewhere in the solar system and, most likely, are common in other star systems.
Category: Chemistry -
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December 2016 - January 2017
Regulation of active ingredient content in tablets
We began to use individual tablets of over-the-counter (OTC) consumer products as samples for some introductory analytical chemistry experiments in 2006.
Category: Feature Chemistry Article -
October 2016
Salty pictures
This summer I encountered two photos of salt that I would like to share with readers; both are of the salt from the Sifto mine in Goderich, Ontario. The mine extends under Lake Huron and is the world's largest underground salt mine.
Category: Chemistry -
September 2016
Gadolinium in MRI contrast agents
Why is the heavy metal element gadolinium utilized in MRI scanning? Is there any chemistry involved? Yes. Read on.
Category: Feature Chemistry -
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March 2016
Iohexol — a CT scan contrast agent compound containing iodine
ER doctor: We want a CT scan. You will be receiving an intravenous CT contrast agent. Patient: What is the CT contrast agent? ER doctor: Iohexol.
Category: Chemistry -
February 2016
Making chemistry relevant to indigenous peoples
In Canada, one challenge is to excite indigenous peoples about science, and chemistry in particular. For many years, with a series of student colleagues, we have been taking a Chemistry Show to schools in remote communities in western and central Newfoundland, coastal Québec, Labrador and even Nunavut (see References).
Category: Feature Chemistry Series Chemistry and Inuit life and culture -
December 2015 - January 2016
Negative temperature?
And then it happened — I came across an online article that caused me to doubt what I had always believed. The headline read “Quantum gas goes below absolute zero”. The January 2013 Nature.com story reported on a published Science article in which “researchers have reached sub-absolute-zero temperatures with an ultracold quantum gas made up of potassium atoms”.
Category: Feature Chemistry -
December 2015 - January 2016
Critical pH and Le Châtelier: How everyday substances and habits can dissolve your teeth away
We know that acids dissolve our pearly whites, but where does this acid come from and what chemistry is really going on in our mouths to make this happen? If your mouth hosts biofilms of certain bacteria, especially Streptococcus mutans that are feeding off sugars, the teeth will be in contact with acid.
Category: Chemistry -
November 2015
Salt in the American Civil War
In his novel Cold Mountain, Charles Frazier describes the hardships that civilians and soldiers alike endured during the American Civil War (or, War Between the States, depending on your side of things). On page 79 of the book, the author describes how two women barter for food.
Category: Chemistry -
November 2015
Chemicals in the news
Phosphine gas has been making headlines in recent months with news stories such as “Phosphine pesticide used to kill bedbugs causes Fort McMurray baby's death”, and “Phosphine gas likely cause of Thailand deaths of Quebec sisters: coroner”.
Category: Feature Chemistry -
November 2015
The ASA tablet bottle quiz and challenge
Those who take a daily, low-dose, 81-mg ASA tablet (acetylsalicylic acid) and other pharmaceuticals may be familiar with a small polymer canister in each tablet bottle (Photos right and below). A canister from an Aspirin bottle is shown. Aspirin® is a trademark in Canada, but a generic term for ASA in the US.
Category: Chemistry News and updates -
October 2015
Sublimation of iodine: Rise and fall of a misconception
For years I believed that solid iodine, I2, only underwent sublimation when heated at atmospheric pressure. I was so wedded to this idea that I performed the demonstration for years.
Category: Feature Chemistry -
October 2015
Not just red eyes and it’s not just the pee
In June 2015 to start the school summer vacation, the Globe and Mail published an article called “Pee, not chlorine, causes red eyes from swimming pools: CDC.” This article may have “grossed out” some, but I looked at it as an opportunity to engage in some real-life practical chemistry.
Category: Chemistry -
October 2015
Redox in the news
On July 7, 2015, the website Phys Org reported on a study that found why the bright yellow pigments of paintings like "The Joy of Life" by Henri Matisse are no longer as vibrant.
Category: Feature Chemistry -
October 2015
A revolution for feminism in France
On March 12, 1962 a revolution shook the French Académie des Sciences. The first woman. Marguerite Perey (1909–1975), discoverer of the alkali metal francium (atomic no. 87), the last naturally occurring element to be discovered, was elected (Fig. 1 & 2) to the venerable institution.
Category: Chemistry -
September 2015
Bismuth in pharmaceuticals: more than Pepto-Bismol
Consulting the print edition of the Canadian Compendium of Pharmaceuticals and Specialties1 (CPS) for the product monograph of the drug Bisoprolol, my attention strayed to the immediately preceding entry Bismutal...
Category: Chemistry -
March 2015
Chemical in the news: Osmium tetroxide
Osmium tetroxide has made the news in Canada and worldwide when Christopher Phillips, a Halifax man, was charged with possession of a dangerous weapon. In January 2015, the Royal Canadian Mounted Police found “floor to ceiling” stacks of chemicals — many unlabelled. One chemical that was identified in the new reports was osmium tetroxide.
Category: Chemistry Recommended Links2 -
February 2015
What colour is P4?
What colour is tetraphosphorus, white phosphorus (WP)? This might seem to be an obvious question, but the answer is not so clear. The Wikipedia entry for phosphorus1 states the commonly-accepted view that...
Category: Chemistry -
February 2015
Should we upgrade photosynthesis and grow supercrops?
This is the title of an online opinion column by Michael LePage which was published in the October 4, 2014 issue of New Scientist magazine under the title “Turbocharge our plants”.
Category: Chemistry -
December 2014 - January 2015
Natural gas (methane) and propane as fuel gases
The use of natural gas (methane) and propane as fuel gases exemplifies numerous areas of general science and general chemistry: intermolecular forces, states of matter and changes of state; heats of vaporization; liquid–vapour equilibrium and vapour pressure; stoichiometry and heats of combustion; gas laws; carbon dioxide emissions and climate change.
Category: Chemistry -
November 2014
Acid-base titrations with citric acid: part 1
Citric acid is a user-friendly, inexpensive, water-soluble, crystalline solid carboxylic acid. In comparison to using hydro-chloric acid solutions, using solid citric acid and its solutions in water is safer and more convenient. For inexperienced students its titrations against strong base are easier to perform.
Category: Chemistry -
October 2014
An 1860 blood test for you to try
In medico-legal inquiries, it is often of the utmost importance to determine the character of red spots on linen or steel, supposed to be blood stains. M. Brucke has recently published the following method, as being superior to those in common use: – ‘Wash the spot with cold distilled water. To the reddish liquor thus obtained add a solution of sea salt, and evaporate to dryness, in vacuo, over a vessel containing sulphuric acid...
Category: Chemistry -
October 2014
Chemicals in the news
Azodicarbonamide has recently received a lot of attention when the sandwich chain, Subway®, announced its plans to remove this compound from its bread. The compound was used to improve dough and maintain bread texture.
Category: Chemistry -
September 2014
Stop, drop and roll
On February 19th this year I picked up my Globe and Mail from the doorstep and saw on the front page a horrendous image of a man desperately trying to protect his face with his hands as flames encircle his neck. You can see that the initial burns were just small sparks on his jacket (which must have been very flammable). The flames flared upwards from these sparks toward his head.
Category: Chemistry -
September 2014
Why is my tire flat?
This has been a very cold winter (written in February 2014). One cold morning I noticed that my car tires seemed very “flat”. Here is a cold weather gas law question for your students.
Category: Chemistry -
May 2014
A strange factoid about a zinc supplement
Seeking to calculate the percent by mass of the active ingredient in a tablet of zinc mineral supplement, an interesting fact was discovered. The zinc supplement is manufactured by Jamieson Laboratories of Toronto; the label amount is 10 mg zinc.
Category: Chemistry -
May 2014
Taking the poisonous bite out of cyanide and avoiding other poisons
Unless you’re a falsely accused, innocent bystander at the scene of a crime, coincidences can be fun in life. I was demonstrating the reduction of permanganate ion (MnO4-) by thiosulfate ion (S2O32-) to my students.
Category: Feature Chemistry -
May 2014
Chemicals in the news
On April 2, 2014, a chemical explosion at the Greenbrook water treatment plant in Kitchener, Ontario, shook the neighbourhood. A chlorine tank exploded when it was filled with ammonia, leaving a strong chemical smell in the air. Officials said no one was injured in the explosion.
Category: Chemistry -
April 2014
Organic molecules of everyday life.12. Triclosan
This series of articles considers some common organic molecules that we encounter in our everyday lives. Described will be some general chemical information about the organic molecule, how it is useful to us and other interesting facts.
Category: Feature Chemistry -
April 2014
Is aluminum amphoteric? A picture is worth 1 x 10^3 words
After I read Myra Hauben’s interesting piece in the February 2014 Chem 13 News (page 8), I duplicated the reaction of a paint-free — the paint was sanded off — soda can in 6 mol/L NaOH(aq), side-by-side with the reaction of another can in 6 mol/L HCl(aq). The results are similar — see adjacent photo.
Category: Feature Chemistry -
March 2014
Forget about saving the planet, I just want to eat my snacks in peace
I first took notice of PLA (polylactide or poly-lactic acid) polymers in the summer of 2009 while vacationing at our family cottage. There, most evenings included a campfire, some conversation, occasionally even a song, but on this night the peaceful sounds of a summer evening came to an abrupt halt with an ear-splitting crackle.
Category: Feature Chemistry -
March 2014
Para-Chlorobenzotrifluoride (PCBTF) – the ‘super-solvent’
How many of you have heard of para-chlorobenzotrifluoride (PCBTF)? Or to give it a more systematic name, 1-chloro-4-(trifluoromethyl)benzene. In a previous article, I described the hazard of the xylene-ethylbenzene hydrocarbon mixture often used as a solvent in varnishes and glues.
Category: Chemistry -
February 2014
Xylenes — A cautionary tale
As chemical educators, we are always thinking of potential hazards in the chemistry laboratory. But it is easy to overlook potential hazards elsewhere in our lives and in the lives of our students.
Category: Feature Chemistry -
December 2013 - January 2014
Organic molecules of everyday life. 11. Frankincense and myrrh
This series of articles considers some common organic molecules that we encounter in our everyday lives. Described will be some general chemical information about the organic molecule, how it is useful to us and other interesting facts.
Category: Feature Chemistry -
December 2013 - January 2014
Measuring CO2 at Mauna Loa
An article called “Measuring CO2 in the atmosphere” in the March 2010 issue of Chem 13 News describes how and where measurements of the atmospheric concentrations of CO2 are taken. Lew Brubacher, the author, explains that Mauna Loa is one of the locations where measurements are made because of its high altitude, 3,400 m, and its distance from any vegetation or industrial activity.
Category: Feature Chemistry