Pure Water’s pH is only 7.00 at a Specific Temperature.

Pure water’s pH is only 7.00 at a specific temperature of 25.0 °C.  Students (and teachers too) hear that number so often that they forget where it comes from. And forgetting its origins makes one forget that if the temperature deviates significantly from 25.0 °C, you will get unfamiliar numbers for the pH of pure water.

At any temperature, pure water will always have the same concentration of ions resulting from a very slight splitting of the life-essential molecule into a positive hydrogen ion and a negatively charged hydroxide ion. The product of each ion’s concentration will equal its so-called Kw of 1.01 × 10-14 at 25.0 °C. To calculate the concentration of H+ ions, you first take the square root 1.01 × 10-14  and then take the negative logarithm of H+, the definition of pH. It yields 7.00.

But changing temperature usually affects any equilibrium constant, including Kw. In this case raising temperature helps water split up. You get more ions, thus a higher ion product. Kw becomes 5.48 × 10-14 at 50 ° C, Lowering the temperature has the opposite effect on equilibrium, and Kw becomes 0.29 × 10-14 at 10° C.

When you recalculate pH of pure water at 50 ° C and 10° C, we obtain pH’s of 6.63 and 7.27, respectively. The temperature does not make water either slightly acidic or alkaline. It’s just that the middle or neutrality point of the pH scale at those different temperatures changes. The 7.00 is not set in stone. The middle point of the pH scale is a setting derived from what the Kw happens to be at 25.0° C.


The pH is also 7.00 for aqueous solutions whose solutes at that same temperature do not affect the ions that water itself produces. When the temperature changes for those solutions, the pH will change accordingly. In our bodies, if temperature was the only factor, then out physiological pH would be below 7.00. But the presence of bicarbonate ions eats up some of the hydrogen ions, setting the physiological pH at about 7.4. The  pH of the extracellular fluid of tumour cells, as determined by probing microelectrodes, is acidic. That truth has been known for at least 3 decades, and of course nothing one eats will have any impact on the pH of that fluid.

Often teachers have to reiterate to get ideas across. So indulge me. 🙂 Does temperature affect neutrality of pure water? No. The concentration of hydrogen ions will be equal to that of hydroxide ions as long as no solute interferes with one of them. Does raising temperature raise the concentration of OH? Yes. Of H+? Yes. Will that in turn affect pH? Of course, by definition.


Science Outreach: Two Ends of the Spectrum

CokeMost readers are familiar with the term greenwashing in which certain companies use the jargon from the environmental movement on their label to boost sales. But meanwhile, with regards to packaging and/or manufacturing, they do not implement the ecological practices required to significantly cut waste and pollution.

The worst form of science outreach is actually science-washing. Science-washers make it seem like their sole objective is to enlighten people about the science surrounding an issue. But in reality they are more concerned with self-interest and/or some economic or political objective.  The world of science media is filled with little fires, issues that seem potentially threatening.  In some cases, science can tell immediately if they are staged. But science cannot always tell which of the real fires will die out by themselves and which ones will grow to be devastating. But the science-washer will act 100% certain when some inner belief or vested interest is threatened.

I have notes regarding a 7-year old Montreal Gazette newspaper article about the endocrine disruptor, bisphenol A (BPA). It started with the line, “Relax – food chemicals can’t hurt you.” That was one heck of a general assertion! Did the author, who is a well-known educator and media personality to this day,  forget things like the botulinum toxin, a chemical that can show up in food that hasn’t been preserved properly. Of course incidences of botulism are rare, but the compounds glucose, sucrose, sodium chloride and sodium nitrite are common additives and are far from being innocuous.

There are enough people out there who hate nuances. They will tolerate details as long as there is a clear-cut answer at the end of a short article. The author of The Gazette article did not disappoint. He totally dismissed the concerns about the particular endocrine disruptor. Unfortunately, he failed to mention that there were other compounds in its class, some far more powerful, and that even at that, he failed to look at the problem ecologically where, for example,  extremely low doses had effects on fish.  The Centers for Disease Control and Prevention website currently(2020) states:

Human health effects from BPA at low environmental exposures are unknown. BPA has been shown to affect the reproductive systems of laboratory animals. More research is needed to understand the human health effects of exposure to BPA.

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Ed Elmos and the real Jaime Escalante in Stand and Deliver 

My criticism of his article was online. How he quickly found out about it was a mystery to me at the time, but the important thing is what he whined about. He said that the details I provided, although accurate, would have confused the public. Here was an educator forgetting the famous line from  Stand and Deliver based on a real-life outstanding teacher, Jaime Escalante who said, “Students will rise to the level of your expectations.”

I wish that article was an isolated incident. There are many people with academic credentials online who blur the line between science outreach and just straight-out public relations. For example, defenders of the health and ecological safety of glyphosate or Enlist Duo’s (glyphosate + 2,4-D and other additives), never get into the nuances. Try arguing with them. When they realize that you are not a communist, anti-vax, anti-science or even an activist, they will try persuade you with bizarre conspiracy theories that smear reputable journalists and the International Agency for Research on Cancer (IARC).

So what does excellent science outreach look like? It looks like the Youtube series Sixty Symbols from the University of Nottingham.  These guys are the real McCoy. Why?  They are not trying to sell you nuclear power or a bigger particle accelerator or the misconception that science is the only way of acquiring knowledge. They are genuinely teaching you one way of looking at the world, and it’s obvious that they have put a lot of effort to step away from their research or other activities to make their knowledge more accessible. In one video by Phil Moriarty, I saw a completely original way of teaching the uncertainty principle.

An extended musical note versus a short one. The frequency range of the latter is wider. This is related to the uncertainty principle.

It is counter-intuitive but true that a short musical note (like the one created when you chug an electric guitar string to stop it from vibrating) has a wide frequency range. In contrast, if you whistle the same note for an extended period of time, there is just one frequency. Frequency and time are inversely proportional. The momentum of an atomic sized particle, which has significant wave properties, is a kind of spatial frequency. If the wavelength is short, like that of the abrupt musical note, there are a number of possibilities for momentum. If the wavelength is longer, the momentum is known with more certainty, but the particle’s exact location becomes much harder to pin down. It’s stretched like the extended whistle.

When the Nottingham physicists are asked about how well-prepared students are for university physics, they don’t get into a whining session. Given that they are genuinely committed to student-learning, they give constructive criticism. They point out that the topics covered by A-Levels physics teachers (in England) are adequate, but that the math courses are a bit broad in scope and exam-centered with not enough rigorous calculus. It is an important point that, if addressed, will help students as much as it will help professors. In contrast, those who do poor outreach rarely give useful tips. One particular individual, who went on to work for the front group ACSH, once criticized an article revealing that lots of science Nobelists are alumni of public high schools. Why? He worried about the bad impression it would make on private schools.

Authentic and quality outreachers are not afraid to show the human face of science. In Falsifiability and Messy Science, another Sixty Symbol video, ( maybe go for a coffee during the Master Class advertisement by Neil Tyson!) Phil Moriarty argues that there is no clear-cut definition of science. Different teams have different approaches. They don’t necessarily seek what’s falsifiable (a la Karl Popper), and are not always looking to verify hypotheses. They are often poking around, trying to find something.  And yet they still produce science that’s valuable and reproducible. Later, when he mentions that science, like all human behaviour, is not only determined by rational thought but by social context, the interviewer takes exception, “Aren’t you stoking the fires of people like climate change deniers?” Moriarty countered that although he looked at some of the evidence for man-caused climate change and found it strong, he is ultimately convinced of the phenomenon by having faith in specialists’ opinions.

Although Moriarty doesn’t delve into the issue, what’s relevant is that it’s also perfectly reasonable and necessary to consider conflicts of interest. What makes man-caused climate change increasingly convincing to the majority, is that it has far less hidden and/ or dubious motives than those of the skeptics. It is for the same reason that I take the President’s Cancer Panel seriously when they concluded in 2010:

“the true burden of environmentally induced cancers has been grossly underestimated” and strongly urged action to reduce people’s widespread exposure to carcinogens.


A Dozen+1 Visions of the Future

Between 13 and 20 years ago, I made a combination of humorous and pretentious predictions. Typically, these ventures reveal one’s biases more than they reveal the future. But I reprint them here because I hope you will find some of the writing full of, if nothing else, zest.

1.  In the last five decades of the twentieth century, prized “free time” was in principle supposed to allow people to derive more pleasure out of life. But people had allowed themselves to fall into more traps during their most precious hours. For instance, in order to create more leisure, they would pay people to mow their lawns and shovel their driveways. And rather than take a time-consuming walk to the grocery store, they would take their cars. But of course by doing so they found that they were not getting enough exercise, so they chewed up part of their leisure hours by joining health clubs to fiddle with dull and costly machines.

In that same time period, wifi and downloadable movies mushroomed on an astronomical scale because people had no time to engage in storytelling or thoughtful conversations. Without the patience and the energy to plan for adventures, and by engaging in limited concrete activities, they had wasted too much of their leisure in adolescence watching television or their telephones. Bereft of imagination and without an eventful agenda, they had to live vicariously through Hollywood’s products.
how-to-get-your-photo-taken-at-the-iconic-western-brook-pond-fjord-2But all of that had changed by 2036. The way people looked at leisure had been revolutionized. Megaplexes and Nautilus clubs were closing daily. People strolled regularly, admiring foliage, observing scars on pruned trees, and examining stars and planets above them. They raked their own leaves and indulged in cultivating gardens, growing the showiest flowers and juiciest vegetables; they hiked and cross-country skied in empty lots and forests and swam in ponds and seas. And they always took the time to share their experiences with friends and family in the form of fireside stories and handwritten letters.

2. CaptureEven in China, people had given up tobacco by the year 2035. Instead, many people “smoked” math and science. Teenagers would typically carry rolled up brain-teasers in cigarette-sized packages and would distribute them among friends, sharing creative solutions to frown-inducing puzzles. The prospect of being able to do math well into their ripe years made the young less fearful of aging. As a result, they no longer had reason to be rude to the elderly or to commit themselves to an early death by smoking cancer sticks.

3.  downloadBy the year 2034, a concrete version of Geocities‘ virtual world had become a reality. A new suburb was created out of neighbourhoods that were based on general interests, from sculpture to sports. In the sculpture neighbourhood,for example, there was art at every corner, and workshops were given weekly at community centers. If one wanted to talk about the history of the craft with a retired gentlemen sitting on his porch, all one had to do was walk through the particular neighbourhood. A longer stroll would take one out of that realm, and into a different sphere of human activity. All in all, the real Geocity was at least as intellectually diverse as the computerized version, and in addition it provided people with far more exercise and actual human contact.

4.  CapturteTwo important viral strains were identified in the year 2039. The first, ITOS,had been especially rampant in the 1980’s and 1990’s. Lodging itself in specific pathways between the cerebral cortex and brain stem, it was responsible for the urge to create workshops and seminars for white collar workers. ITOS was especially effective because of the action of its companion-virus, SIBS, which over a short period of time made people even more likely to accept untested ideas in education and industry. Since the viral epidemic, millions of dollars and worker hours had been surrendered to gurus who roamed the continent, preaching about high-school semestrial courses and downsizing. But once the vaccination program was launched in the spring of 2039, these gurus found themselves in unemployment lines, without even the urge to persuade those ahead of them to let them pass.

5. By the year 2040, virotherapy used cancer-killing viruses with the following characteristics:

(1) Captwqdurethey proliferated only in cells with Ras-gene signalling pathways or in those with excess protein-growth factors—in other words only in cancer cells and not in normal cells.
(2) they continuously changed their protein coat, preventing the human immune system from attacking these viruses before they had a chance to eliminate tumours.

In spite of these advances, some human tumours were resistant to virotherapy. Society as a result continued to invest in preventive medicine by:
(1) carefully controlling carcinogenic compounds in consumer goods and work sites and imposing stiff penalties on industries that ignored guidelines.

(2) and encouraging consumption of fruits, mushrooms and vegetables rich in antioxidants that were active in vivo and not only in vitro

(3) by leading a physically active life.

6. hqdefaultBy 2041 the WTA and ATP had merged into one. Women tennis stars were able to compete with men by benefiting from a heavy alloy which was used only in men’s rackets to take that boring big-serve out of their game. The ladies’ lighter rackets eliminated gentlemen’s muscular advantage, so that if the latter wanted to beat the opposite sex they had to do so with stamina and finesse, both of which were acquired and not inherited traits.

7. rainMost autistic people, like most people in general, do not have a special talent. A minority, the so-called autistic savants, have a phenomenal memory for specific things such as music, numbers or smells. As a renowned psychologist had pointed out at the turn of the century, it was as if the rest of the autistic brain was overcompensating for its dysfunctional part.Years after, it occurred to educators that in most people, the parts of the brain responsible for social behaviours—the same ones that are limited in autistic patients— are too active, limiting the average person’s capacity for both logical and creative thinking. Through a combination of mental training, proper diet, self-discipline and the release of internal psychoactive substances, people in 2046 became capable of turning the loud voices of fruitless thinking into a feathery whisper. On demand, the brain no longer occupied itself with commercial and political propaganda; when necessary, it shut off thoughts of gossip and finances. It then had far more energy to create art and to listen to the sounds of science.

8. By the year 2047, the LHA class of 2003 had left an indelible mark on the world of science. Forty four years ago they had consisted of a musical talent who laughed a lot, a big guy who temporarily wanted to become a fireman, an artist who for a short time distracted himself with a donut-job, a peace-loving girl who dyed her hair red for the prom, another musical talent who actually read the Crystal Ball reports, a bright girl who could easily persuade her less motivated boyfriend to study, a girl who took caffeine to dance more gracefully, a modest guy who had the most analytical brain the school had seen in the 21st century to date and of many more noteworthy students.

Although they managed to open windows into the neurochemistry behind motivation, musical talent,logic, ambition, and temperament, the LHA class of 2003 found that the brain is like the sky and weather: intricate, beautiful, stormy, partly predetermined, and in the long-term unpredictable. Whether they approached a subject at the level of the organism or at the molecular level, their probes themselves had an impact on the human brain, not to mention the countless other factors that shaped each person along the way. Are all the possible outcomes of personality being played out somewhere in an infinite universe? The other versions of the red-haired girl and her classmates may be unfolding, as we speak.

9. By the year 2032, the world of advertising had crumbled. After a century of “slavery to brand-names”, people became fed up with paying $100 for a pair of shoes that cost $2 to manufacture but $20 to promote. As long as the quality of goods was improved, total sales did not suffer dramatically because of Third World demand. With public opinion behind them, governments were then able to pressure manufacturers in meeting durability and environmental standards, which were funded by capital that in the past had gone into running shoe contracts.

10. 3ureNot too long ago, the crystal ball of science gave us a glimpse of the year 2029. For most of the twentieth century, thanks to chemical pigments in photographs and to fluorescent materials in TV screens, electromagnetic waves from inanimate materials could resemble those bouncing off the people we loved thousands of miles away. Similarly the waves from their voices could be made to disturb the crystal patterns of tiny fragments of iron, which later led to the regeneration of so very similar disturbances on the cardboard of a speaker. But smells and tactile impressions, so unlike sights and sounds in that they involved direct interaction with matter and not energy, could not, for the longest time, be recorded. In 2029 a dream specialist, after understanding the way the brain uses memory to recreate physical feelings and smells in dreams, recorded the perfume and velvety texture of a rose and induced its impressions in the consciousness of a computer operator who had not smelled a flower in 22 years.

11. Only hydrogen and electric cars motored through the streets of Honolulu .There were no tourists parading on their scooters without a helmet. In fact, the streets of Waikiki were relatively quiet. Most tourists came to Oahu to study the geology of the island or to appreciate the interaction of light and water. Only birds slept in Kapiolani Park. The hydrogen-generating plant in Pearl Harbor had rehabilitated and hired all of the city’s homeless people.

12. This month, the crystal ball of science gave us a glimpse of the year 2026. Most states had adopted Vermont’s no billboard law on their highways. Within urban centers, the only billboards found (and there were never more than 2 per acre ) were those containing useful information such as atomic masses and physical constants.

I think that I shall never see a billboard lovely as a tree. Perhaps, unless the billboards fall, I’ll never see a tree at all.

-Ogden Nash

Untitled-1At every major intersection, along with a 911 terminal, there was a 912 terminal, an emergency computer hot line for students stuck on homework problems. We saw a haze over L.A. that slowly but surely dissipated, suggesting that for the first time in 75 years, less than 1000 compounds diffused into its atmosphere. And there were quiet motorcycle gangs wearing T-shirts with elemental symbols on their backs. Street gangs had traded their guns in for periodic tables, and they spent their nights helping little old ladies understand moles and molecules.

13.  The Empathy Assistor was invented in 2043. Using only two consenting participants with a minimum age of 15, for three nights the two people involved would experience manufactured dreams based on each others’ fears, hopes and aspirations. Each person would wake up knowing what went on in the other person’s head and soul as the latter experienced anything from taunting to ice cream, from math to television drama. It was more efficient than any other therapy or method for resolving inter- and intra-personal conflicts. Like most new technologies in the last two centuries, it was embraced too enthusiastically. Even  after strict controls and guidelines, it did not work on some people. The public went back to shaming them until they were reminded to have a little empathy for those who lack the capacity.


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