Tag Archives: Chemistry

Lamentations on Science Infotainment Rev 2.

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Note: This post appeared May 15, 2007, as “Infotainment, Chemistry, and Apostasy“. I have pulled it up through the mists of time for another go and with a few edits.

In the normal course of things I used to give school chemistry talks or demonstrations a couple of times per year and until recently, I had been giving star talks at a local observatory more frequently.  The demographic is typically K-12, with most of the audience being grades 3-8.  From my grad student days through my time in the saddle as a prof, I was deeply committed to spreading the gospel of orbitals, electronegativity, and the periodic table. I was convinced that it was important for everyone to have an appreciation of the chemical sciences.  I was a purist who knew in his bones that if only more people were “scientific”, if greater numbers of citizens had a more mechanistic understanding of the intermeshing great world systems, the world could somehow be a better place. 

In regard to this ideology that everyone should know something about chemistry, I now fear that I am apostate.  I’m a former believer.  What has changed is an updated viewpoint based on experience.  

Let me make clear what science is not. It is not a massive ivory tower that is jealously guarded ajd intended to be impenetrable by mortal folk. Big science requires big funding and organizational support, so big administrative structure forms around it. At its core, science is concerned with learning how the universe works by observation, constructing a good first guess (theory) on what is happening, measurement (conducting quantitative experiments), analysis (quantitative thinking), documentation and communication. The common understanding is that a scientist is someone who has been educated and employed to do these activities. However, anyone who conducts a study of how some phenomenon happens is doing science whether for pay or not.

What science has learned is that the universe is quite mechanistic in how it works. So much so that it can be described by or represented with math. At the fundamental level of ions, atoms and molecules, constraints exist on how systems can interact and how energy is transferred around. At the nanometer-scale, quantum mechanical theory has provided structure to the submicroscopic universe.

Chemical knowledge is highly “vertical” in its structure.  Students take foundational coursework as a prerequisite for higher level classes.  Many of the deeper insights require a good bit of background, so we start at the conceptual trailhead and work our way into the forest. But in our effort to reach out to the public, or in our effort to protect a student’s self-esteem, we compress the vertical structure into a kind of conceptual pancake.  True learning, the kind that changes your approach to life, requires Struggle.

What I found in my public outreach talks on science- chemistry or astronomy- was the public’s expectation of entertainment. Some call it “Infotainment”.  I am all in favor of presentations that are compelling, entertaining, and informative.  But in our haste to avoid boredom, we may oversimplify or skip fascinating phenomena altogether. After all, we want people to walk out the door afterwards wanting more. We want science to be accessible to everyone, but without all the study.

But I would argue that this is the wrong approach to science.  Yes, we want to answer questions.  But the better trick is to pose good questions.  The best questions lead to the best answers. People (or students) should walk out the door afterwards scratching their heads with more questions.  Science properly introduced, should cause people to start their own journey of discovery. Ideally, we want to jump-start students to follow their curiosity and integrate concepts into their thinking, not just compile a larger collection of fun facts. 

But here is the rub. A lot of folks just aren’t very curious, generally.  As they sit there in the audience, the presentation washes over them like some episode of “Friends”.  I suspect that a lack of interest in science is often just part of a larger lack of interest in novelty.  It is the lack of willingness to struggle with difficult concepts.  But that is OK.  Not everyone has to be interested in science.

Am I against public outreach efforts in science?  Absolutely not.  But the expectation that everyone will respond positively to the wonders of the universe is faulty.  It is an unrealistic expectation on the 80 % [a guess] of other students who have no interest in it. I’m always anxious to help those who are interested.  It’s critical that students interested in science find a mentor or access to opportunity.  But, please God, spare me from that bus load of 7th graders on a field trip. 

What we need more than flashier PowerPoint presentations or a more compelling software experience is lab experience.  Students need the opportunity to use their hands beyond mere tapping on keyboards- they need to fabricate or synthesize. You know, build or measure stuff. 

It is getting more difficult for kids to go into the garage and build things or tear things apart.  Electronic devices across the board are increasingly single component microelectronics.  It is ever harder to tear apart some kind of widget and figure out how it works.  When you manage to crack open the case what you find is some kind of green circuit board festooned with tiny components. 

And speaking of electronics or electricity, I find it odd that in a time when electric devices have long been everywhere in our lives, that so FEW people know even the first thing about electricity. I instruct an electrostatic safety class in industry and have discovered that so very, very few people have been exposed to the basics of electricity by graduation. I spend most of the course time covering elementary electrostatic concepts along with the fire triangle so the adult learners can hopefully recognize novel situations where static electric discharge can be expected. Of course, we engineer away electrostatic discharge hazards to the greatest extent possible. But if there is a hole, somebody will step in it. It’s best they recognize it before stepping into it.

The widespread educational emphasis on information technology rather than mechanical skills ignores the fact that most learners still need to handle things. There is a big, big world beyond the screen. A person will take advantage of their mechanical skills throughout their life, not just at work. Hands on experience is invaluable, in this case with electricity. Computer skills can almost always be acquired quickly. But understanding mechanical, electrical and chemical systems need hands-on experience.

Learning Chemistry and Struggle

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A few thoughts on struggle in learning. I’ll confess to having taught undergraduates in the classroom and the research lab environment. My classroom teaching bona fides are limited to 6 years of college level chemistry lecture/lab and quite a bit of one-on-one chemistry tutoring.

Many students approach college chemistry courses with caution. For some, a year of freshman general chemistry is mandatory for their major. Majors such as pre-med, physical therapy, and veterinary medicine require organic chemistry in addition to general chemistry. As my specialty lies in organic chemistry, I have experience teaching both general and organic chemistry students..

From my perspective, general chemistry is as much a mathematics course as it is a science course for many first-year students. A significant portion of general chemistry involves establishing and solving problems that necessitate fundamental algebraic manipulations and calculations. Skills such as balancing equations, maintaining units throughout calculations, and understanding significant figures are essential to master. Additionally, there is the challenge of learning the new vocabulary.

Students who managed to avoid chemistry in high school sometimes found themselves treading water in college chemistry and were afraid of taking two 5 credit hour hits to their GPAs. Most pushed on and got through it. General chemistry is a foundation course and is critical for further pursuits in fields related to the use of chemicals. Unfortunately, a year of gen chem doesn’t really make a person able to function as an independent chemist. It is helpful, though, for technicians in a lab doing routine chemical tests.

Gen chem is to chemistry as The Hobbit is to The Lord of the Rings– it is the necessary prelude to a larger story.

A common problem I encountered while teaching chemistry was the desire of some students to give up hope of ever “getting it”. They would hold off attending office hours to discuss their difficulties until it was too far down the semester timeline. This was usually after a few botched regular exams or a low midterm grade. Frequently the struggling student was having trouble with or neglecting the assigned homework from the text.

Now and then you’d run into a prof who had performance expectations that even they might not have met as an undergrad. They’ll strut around acting as though they were singlehandedly maintaining “proper” academic ideals. Who knows, maybe they had a point. You can try to enthuse everyone using words and pictures, but inevitably there are those who are utterly disinterested, inept or just anxious to put chemistry behind them.

In retrospect, I should have been more direct in calling in more students to office hours who were in grade trouble early in the term. Unfortunately, like many other profs I sometimes subscribed to the sink or swim approach to college education where unsuitable students are culled from the herd. It is a sort of Darwinistic mindset that is easy to fall into. In the end, we have to give all students a fair chance or even a second chance to earn the credentials that the institution confers.

Colleges are organizations that award credentials to verify achievement in meeting or exceeding educational standards set by in-house professors. It tells people that you completed what you started: you navigated a complex maze of intellectual achievements and came out the other side a success.

For any given subject there are always those who struggle with it to some extent. It could be from simple boredom, distractions from real life or the comprehending of difficult material. It may be that the subject just isn’t for them. For myself, I struggled with a foreign language and eventually gave up. I needed full immersion and that wasn’t going to happen. I still regret giving up.

One problem that can often be addressed, however, is the matter of struggle. It seems that many students are not accustomed to struggling with learning. All of us have learned particular subjects successfully because it “just fit” our cognitive abilities, interest or perhaps it was brilliantly presented to us. Or it was a special time in our lives when we were uniquely receptive. It could very well be that previous exposure to the subject was a bit shallow with grade inflation, leading to overestimation of their abilities.

Unfortunately for some, the very necessity of struggle convinces them that the subject is beyond their abilities. They come to believe that if the subject does not immediately stick or appear obvious, then they might as well give up because they will never “get it” along with a collapse of self-esteem.

Giving up on a subject early-on could allow them to switch directions in their education with less time lost and perhaps they would be relieved by that. In this case, giving up is just making a better choice based on experience. Regardless, students should be unburdened early on of the idea that struggle is a predictor of failure. In reality, most learning involves struggle at least to some extent.

Remedies for Struggle

Reading the assigned chapters several times is helpful. First pass, scan the content for a general idea of where the topic is going. A careful reading next with a focus on the example problems is very helpful. Try to understand the example problems and the reasoning presented. Next work on the problem set. If there is time, a third reading can help to cement in the concepts in the chapter. Before going on, work on the assigned problems. Open the solutions manual only if stuck. Struggle with the problem a bit. Success with solving assigned problems can be extremely helpful for a student.

If laboring alone isn’t helping, some schools have tutoring resources available. If not, there are often tutors who will charge on an hourly basis. A few hours of tutoring may be all it takes to get back on track. Sometimes there may be study partners from your class who can study with you. Then again, office hours with your prof or TA can help you over some rough spots. The point is- Struggle!

When I was writing exams, I would look at the example problems in the text as well as the assigned problems. I chose the problems to assign because I felt that they got to the heart of the concepts I held as important to the subject at the level of the content. I would use the assigned problems or those from lecture to write problems using different substances where a reaction would lead to an unambiguous answer. It’s ok to write some questions that require bit of logic to solve, but you can’t turn the exam into an intelligence test.

I once taught a course in chemistry for non-majors. These were students who had tried to get into Geology for Poets or Astronomy but couldn’t get in. They were trapped into taking chemistry for their science requirement for graduation! Early on, a few “representatives” of the class cornered me after a lecture and informed me that “everyone” expected true/false questions on the exams. Pausing, I said I would give them true/false questions, but they would get 1 point for a correct answer, 0 points for no answer, and -1 point for an incorrect answer. The lesson was that if you don’t know something it might be better to just be quiet. After a single exam they never mentioned true/false questions again.

Students eventually realize that chemistry is a highly vertical subject. The more advanced and interesting concepts are built upon or knitted together from those learned earlier. Later coursework will assume that the student has a grasp of content from earlier prerequisite courses. Thirty-one years later the 95 course evaluations from that Catholic women’s college still sit in an unopened envelope in my office.

Find a way to deal with anxiety. Exercise or find a councilor, psychologist, or psychiatrist for help. Anxiety is “druggable”, that is there are meds for it that are very effective. I’m sure there are exceptions, but a family practice doc can’t go very far down the road in treating anxiety. A psychiatrist can fine tune and mix the individual meds to best suit you. It really works.

Most importantly, the student should not EVER get behind in the coursework. It might even be better to drop the class than try to make up for much lost time. The normal rate of chemistry content flow to be absorbed is already high. To have to make up for time lost while also keeping up with the current content flow is often impossible.

Finally, consider that struggle just means that you have to put forth effort to learn. True learning means that your neurons are making new connections in your brain, not just images of something new. To have learned means that your brain has found a way to take diverse inputs and assemble them into part of your consciousness. Sometimes it isn’t easy, but persistence is the key.

Some Pragmatics of Green Chemistry

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After following a chat room discussion on process safety, I find myself mixed on the matter of what is called green chemistry. In the present example, a fellow wanted to methylate a phenol but didn’t want to use dimethylsulfate or some similar methylating agent. He wanted something that was “green”.

Suggestions were varied, including a recommendation on the use of dimethyl carbonate as methylating agent and a few other approaches through aromatic substitution. One contributor wisely reminded contributors about going into the weeds with low atom efficiency.

“Green chemistry is the design of chemical products and processes that reduce or eliminate the use or generation of hazardous substances. Green chemistry applies across the life cycle of a chemical product, including its design, manufacture, use, and ultimate disposal. Green chemistry is also known as sustainable chemistry.”  -EPA

When green organic chemistry is the goal in synthesis, it pays to be sure that there is an accepted definition of green chemistry on site.  The merits and definitions are explained elsewhere. Difficult questions come up when a non-green substance is replaced with something that may be “more green” but needs 2 steps instead of 1. Or when green but more expensive reagents and solvents are needed. What is best? In this case, greater safety, lower cost, higher space yields, reduced waste generation, and fastest reaction times will be the real drivers. The business to business market will not pay more for a green product while a cheaper non-green alternative is present. If you want to get an existing customer to requalify an existing product from a new green process, be prepared to discount the price in exchange for the customer having to go through a requalification process. Customers do not like change at all.

Under what conditions would management allow a process choice that is greenish but obviously more costly? Possibly never. A greener process needs to give a cost savings somewhere. Barring draconian regulation, a successful green process will have a cost benefit. The benefit may be in lower direct cost of manufacture, satisfaction of a process requirement by a customer, or a hedge against future regulatory restrictions.

Solvents may be one of the easier opportunities for green chemistry. For a given process, there may be a bit of latitude with the solvent. Sometimes the issue of solvent residues in the product may arise. Some solvents are easier to strip away than others. No one will choose a green solvent that is hard to remove from the product. Again, the drivers will be those mentioned above.

Another green opportunity is when we automatically choose a stoichiometric reducing agent when we could have looked at a catalytic system with hydrogen. Catalyst costs per kilogram of product can range from negligible to high. One advantage of using expensive platinum group metal catalysts is that the metal is usually recyclable, which is greenish. However, any organic ligand present does get incinerated producing non-green emissions in the process of energy intensive metal refining. If catalytic hydrogenation requires the installation of new capital equipment, then the installation costs in time and money may prevent a switch.

For green oxidation, oxygen in the air is cheap and abundant but carries a big problem. Using an oxidizing gas in the presence of a flammable liquid reaction mass can give rise to an explosive atmosphere in the headspace of the reactor. This is a non-starter in industry. Catalytic oxidation using a greenish primary oxidant in solution is a good place to start. I’ve heard of hydrogen peroxide or peroxyacetic acid referred to as greenish.

The big problem with green synthetic organic chemistry is that in order to synthesize a molecule, the structural precursors must be sufficiently green, reactive and selective to run on a reasonable timescale and at acceptable cost. And they must not produce non-green side products or wastes that spoil the advantage of the target green step. A weighing of the pros and cons of any attempt to do green chemistry will always be needed and subjective decisions will be made on what constitutes green.

While we are all struggling to be greener, let’s not forget to remind ourselves and others that reduced consumption of almost everything is a green step we can all take right now.

For Students. Thoughts on Chemical Process Scale-Up.

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Chemical process scale-up is a product development activity where a chemical or physical transformation is transferred from the laboratory to another location where larger equipment is used to run the operation at a larger scale. That is, the chemistry advances to bigger pots and pans, commonly of metal construction and with non-scientists running the process. A common sequence of development for a fine chemical batch operation in a suitably equipped organization might go as follows: Lab, kilo lab, pilot plant, production scale. This is an idealized sequence that depends on the product and value.

Scale-up is where an optimized and validated chemical experimental procedure is taken out of the hands of R&D chemists and placed in the care of people who may adapt it to the specialized needs of large scale processing. There the scale-up folks may scale it up unchanged or more likely apply numerous tweaks to increase the space yield (kg product per liter of reaction mass), minimize the process time, minimize side products, and assure that the process will produce product on spec the first time with a maximum profit margin.

The path to full-scale processing depends on management policy as well. A highly risk-averse organization may make many runs at modest scale to assure quality and yield. Other organizations may allow the jump from lab bench to 50, 200, or more gallons, depending on safety and economic risk.

Process scale-up outside of the pharmaceutical industry is not a very standardized activity that is seamlessly transferable from one organization to another. Unit operations like heating, distillation, filtration, etc., are substantially the same everywhere. What differs is administration of this activity and the details of construction. Organizations have unique training programs, SOP’s, work instructions, and configurations of the physical plant. Even dead common equipment like a jacketed reactor will be plumbed into the plant and supplied with unique process controls, safety systems and heating/cooling capacity. A key element of scale-up is adjusting the process conditions to fit the constraints of the production equipment. Another element is to run just a few batches at full scale rather than many smaller scale reactions. Generally it costs only slightly more in manpower to run one large batch than a smaller batch, but will give a smaller cost per kilogram.

Every organization has a unique collection of equipment, utilities, product and process history, permits, market presence, and most critically, people. An organization is limited in a significant way by the abilities and experiences of the staff who can use the process equipment in a safe and profitable manner. Rest assured that every chemist, every R&D group, and every plant manager will have a bag of tricks they will turn to first to tackle a problem. Particular reagents, reaction parameters, solvents, or handling and analytical techniques will find favor for any group of workers. Some are fine examples of professional practice and are usually protected under trade secrecy. Other techniques may reveal themselves to be anecdotal and unfounded in reality. “It’s the way we’ve always done it” is a confounding attitude that may take firm hold of an organization. Be wary of anecdotal information. Define metrics and collect data.

Chemical plants perform particular chemical transformations or handle certain materials as the result of a business decision. A multi-purpose plant will have an equipment list that includes pots and pans of a variety of functions and sizes and be of general utility. The narrower the product list, the narrower the need for diverse equipment. A plant dedicated to just one or a few products will have a bare minimum of the most cost effective equipment for the process.

Scale-up is a challenging and very interesting activity that chemistry students rarely hear about in college. And there is little reason they should. While there is usually room in graduation requirements with the ACS standardized chemistry curriculum, industrial expertise among chemistry faculty is rare. A student’s academic years in chemistry are about the fundamentals of the 5 domains of the chemical sciences: Physical, inorganic, organic, analytical, and biochemistry. A chemistry degree is a credential stating that the holder is broadly educated in the field and is hopefully qualified to hold an entry level position in an organization. A business minor would be a good thing.

The business of running reactions at a larger scale puts the chemist in contact with the engineering profession and with the chemical supply chain universe. Scale-up activity involves the execution of reaction chemistry in larger scale equipment, greater energy inputs/outputs, and the application of engineering expertise. Working with chemical engineers is a fascinating experience. Pay close attention to them.

Who do you call if you want 5 kg or 5 metric tons of a starting material? Companies will have supply chain managers who will search for the chemicals with the specifications you define. Scale-up chemists may be involved in sourcing to some extent. Foremost, raw material specifications must be nailed down. Helpful would be some idea of the sensitivity of a process to impurities in the raw material. You can’t just wave your hand and specify 99.9 % purity. Wouldn’t that be nice. There is such a thing as excess purity and you’ll pay a premium for it. For the best price you have to determine what is the lowest purity that is tolerable. If it is only solvent residue, that may be simpler. But if there are side products or other contaminants you must decide whether or not they will be carried along in your process. Once you pick a supplier, you may be stuck with them for a very long time.

Finally, remember that the most important reaction in all of chemistry is the one where you turn chemicals into money. That is always the imperative.

Learnings from a career in chemistry.

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I will be retiring from industrial chemistry in early 2023. Retirement has snuck up on me, to be honest. I suppose like most 64 year-olds I have trouble recognizing myself in the mirror. The joys and battle scars from my youthful early career are still fresh in my memory even as I turn the corner into the doddering years. I still recall most of the sights and smells and people in the years leading up to the present. I was lucky to meet many good people and unlucky enough to encounter a few problematic jerks. One of my earliest lessons was that not every scientist is one of your brethren. Science contains a bell curve of people- skewed to the good side for the most part, but there are always toxic characters around seemingly bent on making life difficult.

My entry into chemistry was a bit of an accident. I entered college as a physics major and Air Force ROTC minor at the age of 22. Naively I thought that my freshly issued pilots license and an intended physics degree would grease the skids into a flying career in USAF. Boy was I wrong. If anything there was palpable contempt for the pilots certificate. The curious attitude was if you didn’t learn to fly in the USAF then you weren’t shit. Turns out that I was also nearsighted so I was automatically disqualified from a pilot slot. My view in turn became that if you can’t fly jets why be in the USAF?

I took freshman chemistry in the summer for the physics major, then in the fall of my freshman year I started organic chemistry just out of curiosity. I was always puzzled about how drugs work and organic chemistry seemed to be the key. It turned out that organic chemistry was uniquely suitable for my type of ape brain. Soon I switched to a chemistry major and out of ROTC and never looked back at the smoldering crater of my flying career. That said, airplanes are still a passion of mine.

From this end of my career I can look back and see some mistakes I made in the past. First, while I chose a good PhD advisor, I may have aimed too low for the postdoc. It limited my opportunities for a better academic career. Always aim high.

I had a succession of four (count ’em) 1-year sabbatical replacement jobs before I got a tenure track slot at a small midwestern college (with an NMR). One year into my tenure track academic position I drove my career straight into a tree by having an escalating argument with the tenured chemistry department chair. After a long and successful career before my arrival, he tragically became a drunk and a failure in the classroom, he came to treat department faculty with disrespect and was an autocrat. All of this was well known in the department. My mistake in handling the personality conflict was to push a little too hard for near term change in department norms rather than playing the long game by waiting for his retirement. Unfortunately there was no support from the Dean despite the chair’s history of bad behavior. Seeing no help from admin, at Christmas break of the second year I took the first industry job offer I got and left the college. There was no hope for a new contract. I consider this episode to be my fault entirely for not being savvy enough to play the politics right. It was a mistake I would not make again. Oh yes, he died a year after I left.

Lesson No. 1. Learn to engage in politics calmly and ethically. Be patient and smart about it. Abstaining entirely from politics is the politics of victimhood. Like the old saying goes, if you put two people in a room you have politics. If it’s going to happen anyway, you may as well be good at it.

Believing that my teaching resume was fatally disfigured by this absurd episode, I resolved to move into industry. I joined a startup company that was bringing out new technology for commodity-scale polylactic acid (PLA). I was hired to find new catalysts for the cyclodimerization of lactic acid to lactide (the monomer) and comonomers that would lower the glass transition temperature of PLA. PLA homopolymer has a high glass transition temperature that leads to brittleness under ambient conditions. It was a great job and I took a fancy to polymer chemistry. Unfortunately, 11 months after I joined the company folded and I was on the street. Bringing a new polymer into the market at the commodity scale requires a powerful position in the polymer market which we didn’t have. Worse, we had persistent problems with low molecular weight as the money was running out.

Lesson No. 2. Beware the siren song of startup companies. They often fail.

Losing an academic job and an industrial one in a short interval had me eating a big slice of humble pie. These were dark times. In order to feed the family I took a job as an apprentice electrician working commercial construction sites. I had a good boss and the work was interesting. This phase lasted 6 months.

Not wanting to move across the country again I looked for a local job as a PhD chemist. They were scarce. Passing by pharmaceuticals, I took a risk and got a job in chemical sales at a small local chemical plant. Initially I assumed that my career as a scientist was over. As it turned out, that wasn’t true. Most of the chemistry there was multistep organic synthesis so I fit right in. This job would put my chemistry education to use in ways I hadn’t anticipated. We had diverse customers scattered across the world and marketing and customer sales and service required more than just a conversant level of chemistry knowledge in this small market. Very often being able to speak with equal confidence to both scientists and purchasing managers was a necessary skill in making the sale. And the job required some travel to far flung locations which was very stimulating.

Lesson 3. Don’t assume that your career should look like your dissertation project. Be open to possibilities.

Along the lines of Lesson 3, it is worth mentioning that in the course of a chemistry career the chemist might run into the choice of remaining in the lab or transitioning into the business end. The chemical industry requires some business leaders to have a knowledge of chemistry. This should be obvious. The problem is that relatively few chemists enter the job market with solid business credentials. By contrast, chemical engineers evolve their careers by solving chemical manufacturing problems and designing projects within very tight economic constraints. Whereas chemical scientists have a world view that mainly has two axes- space and time- engineers see the world in terms of 3 axes- space, time, and economics. Engineers are trained to bring capital projects in on time and within budget. This facility with projects and economics provides for the facile promotion of engineers to top management positions. My observation is that lab chemists without training in business generally seem to have less career buoyancy than engineers within chemical organizations. Of course there are exceptions. An MBA for a chemist can have real value in upward mobility and lifetime earnings. I’ve seen it happen numerous times.

Lesson 4. The world of chemical business is very interesting and challenging. Give it some consideration.

One way to migrate from the lab to an executive level for a chemist is to become a chief technology officer. This can be a very consequential position in an organization bearing a heavy load of responsibilities. Executive level chemistry jobs can take you into the thin air of business development and the chance to work with a large assortment of executives and managers from other organizations. It is worth aspiring to.

Lesson 5. Polymer chemistry is very interesting. For all you small molecule people out there, try it. You might like it.

But with all of this said, my view now is that I should have tried harder for a flying job in the airlines.