Communicating Data with Periodic Tables

I think periodic tables might just be the most ubiquitous infographic. I have zero data to back up this assertion. It’s just something that chemists use all the time, and most chemists I know tend to have one handy at a moment’s notice, or decorate their offices with them. They never seem to have just one. Even chemistry classrooms tend to have more than one, so I think it’s worth considering the periodic table’s ability to communicate information. Some periodic tables are pretty sparse. Some are hugely information dense (here’s a favorite of mine). And, as a recent article in C&EN points out, although there’s a common shape, there isn’t even a consensus on the “one true way” to arrange a periodic table.

Last May I found this periodic table while browsing through old books in my university’s library.

Periodic Chart of the Elements from inside cover of Gaines, Binder & Woodriff, 1951.

Periodic Chart of the Elements from inside cover of Gaines, Binder & Woodriff, 1951.

It’s from a 1951 textbook (Gaines, Binder & Woodriff), so it’s not terribly surprising that there are fewer elements (96 instead of 118) and some of the symbols have changed (e.g. A for argon, Fa for francium, Cb for columbium, which was later renamed niobium). What made it jump out to me at the time is the arrangement of the table itself: what I’m used to seeing in the middle of the table as the d-block is wrapped around in doubled rows. Copper, silver, and gold are in the same column as lithium, sodium, and potassium! 15 rare earths (La-Lu) are noted in a single cell, but not identified individually, and elements 89-96 are incorporated into the table, rather than segregated on an island of misfit actinides.

I’m told this arrangement was common in the Soviet Union. That it appears in an English-language textbook in 1951 seems interesting, and I wonder if it became less common in the US as the Cold War carried on.

What has struck me since that first look are the choices the creator of this table made about which information to include about each element, and how it’s presented.[1] We have atomic numbers, symbols, atomic weights, and the number of electrons in each shell. But, wait, there’s more: small text at the top of the table explains the horizontal lines running through the table cells:

  • “% area below dotted lines indicates relative ability to lose electrons”
  • “% area above broken lines indicates relative ability to gain electrons”

First, I’m curious now what method or measurement they used to rate ability to gain/lose electrons. Since they are relative quantities, I wonder what they are relative to? (I suppose it’s time to go back to the library and take another look at that old textbook.)

Second, I think the use of the different line styles to convey relative values is a neat trick. They are subtle, yet distinct, and they’re even read from opposite ends of the table cell (area above vs area below). Look along the fourth row (K→Ni) and watch the dotted line drop. You can see the periodic trend in ability to lose electrons! And using the same table you can see the trend in ability to gain electrons!

Several textbooks I’ve used have included figures with the periodic trends as 3D column charts. I don’t love them. 3D charts are really difficult to read because the depth or apparent volume tends to distort the actual differences in size. As a physical object I’d bet they’re useful (like these 3D-printable models), but as an image on a page or screen, I’m not enthused. The periodic table shown above, though, shows two of those trends clearly in a single figure. (Even those 3D printed models show only one trend at a time.) That’s pretty cool.

[1]: As you might guess, I’m a fan of Edward Tufte’s The Visual Display of Quantitative Information.

Molecular tug-of-war: A hands-on demonstration of molecular polarity

Last fall I taught polarity in a different order than I have before. In every previous class, I introduced polarity in the VSEPR unit: first bond polarity, and then molecular polarity immediately after. Instead, last semester, I introduced bond polarity after Lewis structures and tried to get the students in the habit of identifying polar bonds and drawing dipole moments for those bonds alongside their Lewis structures. Then, after working through VSEPR theory, we brought polarity back into the mix. Anecdotally, they seemed to have a better sense of which bonds were and were not polar in the 3D molecules than my previous classes. (I don't know that the order of topics improved their understanding. I suspect it's simply a matter of having had more time to "digest" the idea and practice it more in 2D before moving to 3D.)

Even though they were quite good at identifying polar bonds, the students still had trouble identifying polar molecules. Specifically, they used the simple rule of thumb that if the bonds were polar, the molecule had to be polar, which fails when the symmetry of a molecule is such that the polar bonds all cancel out (e.g. BF3 or CF4).

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A Lab Notebook for Teaching

Chemists are trained to use lab notebooks, whether paper or digital, to record their observations, measurements and preliminary conclusions. Good lab notebooks include not just what you tried, but why you tried it and even what expectations you had for the outcome. Lab notebooks are a record; reading over previous entries can help you notice patterns and plan future experiments. Someone else should be able to read your notebook and understand what, why & how you did everything. Ideally, they could reproduce your work with that knowledge.

Teaching involves a lot of experimentation: choosing examples, refining explanations, developing ways to address misconceptions, rearranging the order of topics, yet few professors I know keep a teaching notebook, even among scientists who would surely defend the importance of a notebook in lab.

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Seeing the syllabus from the other side

I didn't appreciate syllabi when I was a college student. Professors handed out papers of dates and requirements, which they read to us. We stuffed those papers into folders, tucked them in the end pages of our notebooks, or just dropped them in the circular file. Before college I'd never seen a syllabus – we didn't use that term in high school – so it seemed like just another handout, just another piece of paper.

Somewhere along the way I realized that the list of important dates might actually be a useful thing to hang onto and refer back to throughout the semester. The syllabus-readers usually had a leg up on the non-syllabus readers when it came time for projects: we knew they were coming! It was old news for us.

But I still didn't really appreciate those oft-ignored papers until I made one. 

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Plans I wish I didn't need to make

Whenever I'm going to teach in a new classroom, I like to scout it out ahead of time. I want to know if it has a chalkboard or a whiteboard so I can bring the right writing implements. I want to make sure it has enough seats for my class because the classroom capacity according to the registrar and the number of chairs actually present in the room may be quite different. I want to get a sense of the room: find out if it has chair desks or tables, whether late arrivals will disrupt class from the front or sneak in the back, and what the projector situation is. I also like to know that I can just plain find the room! If I can, I go inside and just stand in the front, getting used to the size of the space and the arrangement of the chairs. I like to do this for public speaking, too – I can get over whatever anxiety the foreignness of the room might give me and be more at ease in the now-familiar space when the time comes to talk.

Last week I wandered around campus getting to know the buildings and tracking down the classrooms I'm scheduled to teach in. But I didn't just count the chairs, or decide whether I'll need chalk or dry erase markers. I noted which rooms had furniture that could be piled against the door, which way the doors opened, which rooms had windows into the hallway, and which exits to use if I had to protect my students from a gunman. 

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One year on

This time last year, I was a newly-minted PhD, still revising my dissertation. I had just accepted my job at Briggs, and I was preparing for a conference, a vacation, and a new routine.

I don't remember much of my defense. My parents came to see it, even though it was a Wednesday afternoon and a 10-hour drive from their home. I was sleep-deprived and panicky. I couldn't remember the order of my slides, even though I'd given many variations of that same talk all the way through grad school. When I finished my talk, I cried.

My defense wasn't advertised beyond a poster on the seminar board alongside a dozen other defenses scheduled for the same week. Besides my committee and labmates, almost no one came. I'd been a bit disappointed about this when I started, but that turned to relief and gratitude when I was dabbing my eyes and pulling myself together most of an hour later.

I don't remember what questions the audience asked, and only one of the questions from my committee afterward. One committee member asked for a set of values in a tone of voice that, to me, implied I hadn't done my due diligence. Seeing as that value was highlighted in a table, sleep-deprived me lost patience and told said committee member to read the dissertation. I think I said something like "you'll find that on page 47 in table 2.3," but my internal dialogue was closer to "you obviously didn't bother to read my dissertation," so it's entirely possible that I said something else.

We celebrated in a conference room around the corner from my lab office. My labmates made me a goofy paper hat decorated with pictures of things they associated with me. It was very sweet of them, and moreso because it was a surprise. The hat is now a lab tradition, and I hope it continues. I am Graduate #1. I got to see the start of a lot of lab traditions.

I turned in my dissertation a month later, and continued to work in the lab, wrapping up projects and working on a collaboration up until I left for the conference (and subsequent vacation) in Europe. When I got back, everything was different.

I started at Lyman Briggs College in August.1 It was a new job at a new place, with new colleagues and new students, and I had to learn everything. Where is the copier? What are the college policies? Who do I ask for X or Y? Where to I park my car? What order will we cover the course material in? How deep do we dive into each chapter? How does the course website work? What resources are available? And on and on and on. An overwhelming amount of newness in my environment and also in what was expected of me.

It took me most of the fall semester to get used to being a professor. Some aspects, like delivering lectures, holding office hours, and making copies were familiar. But others -- being the authority the learning assistants turned to, handling grade disputes, offering feedback to colleagues with much more experience than myself -- took a big shift in mindset.

I have learned a lot in the past year. No longer a student, but an instructor, still I continue to grow and learn. Last year, I'd made and given a small handful of lectures. One year on, I've not just delivered 120 lectures to hundreds of students, I've also kept up the routine. When you're a grad student interviewing for a job, you can refine a teaching demo over the course of a week or more. When you're teaching, one awesome talk on Monday is not enough. You've got to be ready for class on Wednesday and Friday as well.

Academia is a flexible place to work. I can grade in my office or at home. I can decide to eat lunch with a friend near home, rather than spending a day on campus. Inspirations for lecture and practice problems can come form anywhere. But academia is also a rigid place to work. When I have a lecture, I must be there. I can't reschedule it. One hundred twenty-five students will be there, whether I am or not. One year on, I'm still getting the hang of this combination of rigidly structured and fully unstructured time.

When I started at Briggs, few people had seriously called me "Dr. Haas." It took a while to get used to; not just the title change (thought it was a much faster transition than when I changed my name after marriage), but the notion that I was a doctor of some sort. I couldn't tell my students to go ask their professor -- that professor was me!

I'd look at Facebook and see friends from high school, college and my time as an exchange student, and I'd see the great things they'd done, places they'd gone, children they'd had, careers they'd built, and I'd think "What have I done with my life?" And then my husband would point out that none of the people in question had doctorates in chemistry, that I'd spent five years in pursuit of that degree, and that I should very much give myself a break.

You see, despite five years of graduate school and all it entailed, it was (and sometimes still is) easy to forget I'd actually gotten a PhD. It's my own flavor of Impostor Syndrome, I guess. That nagging feeling that there'd been some mistake. That I wasn't really good enough for a PhD from a highly ranked university. That they gave me a PhD to get rid of me because they pitied me, but I'd gotten too far for them to kick me out.

One year on, I answer to "Dr. Haas," "Doc," "Professor," and occassionally "Prof Haas" without blinking. I've stopped feeling like the mail room is off-limits, or like I'm a child in an adults-only space. I am less surprised when a colleague asks for my input or feedback.

When I started I feared for the way I'd measure up to stereotypes. I dressed up a little; I wore khakis and slacks. I addressed emails to students more formally than my usual style. I checked and double-checked my work for errors so my students wouldn't see me fail.

One year on, I'm in skirts every Friday. It started as "Formal Fridays" in my mind, but soon became "Fearless Fridays" when I discovered that dressing like myself gave me a confidence boost. I can tackle so much more in my dress boots and a skirt than in my fall semester "uniform."

One year on, I still make mistakes. Having yet to achieve apotheosis, I expect the mistakes will continue. ;-) But I'm learning. I make new and different mistakes, and my ability to make corrections -- and let the students and learning assistants correct me -- can be evidence to my students that you don't have to be right all the time. When it comes to dealing with students, I've relaxed.

Last year my colleagues were strangers. My freshmen hadn't yet graduated high school. I had a plan for only one year. One year on, my colleagues are mentors and friends, my students have settled into college life, and my one-year job is at an end.

It has been a real delight to work at Briggs with such wonderful, supportive, creative faculty (and staff!) and highly motivated students. The students may not all love chemistry, but they do see the value in it. They challenge me and surprise me. They are funny and insightful and earnest. They bring me so much joy. I am sad to go.

But I won't be sad forever. This spring I accepted a tenure-stream position at Misericorida University. I have new colleagues, new students and a new plan. I'm thrilled, even as I start to take farewell of Briggs and MSU. I have more to learn, more ways to grow, and another good place to do it.

So here's to another year. Wish me luck.

1: Lyman Briggs College (aka Briggs) is a residential science college at Michigan State University: all of the students are science majors of one sort or another. In addition to taking intensive, group-focused introductory science and math courses together, the students also take courses on the history, philosophy and sociology (aka HPS) of science. It's a pretty cool place to work, and I'd have loved it as a student there.

Those who can, do. Those who can explain, teach.

My mother is an elementary school teacher. She chose that career path at approximately the age of 12 when writing an essay about what she wanted to be when she grew up. And she stuck to it. She's a Master Teacher, an expert in elementary education with extensive experience in remedial reading and math. She's taught nearly every level of elementary school, and since there aren't as many specialized courses in elementary school, she's taught nearly every subject, too.

My brother and I spent many, many Saturday and summer afternoons in my mom's classrooms, or playing in the empty hallways. She teaches in a different district than we went to school in, otherwise I'm sure we'd have spent even more afternoons and evenings at school. I have many memories of stocking bookshelves, cutting out cardstock shapes, keeping an eye on the laminating machine, sorting counters and tools and toys.

From the age of 12, if not before, I was asked "Are you going to be a teacher like your mom?" I got tired of that question very quickly. No, I was not going to be a teacher. Teaching is a lot of work! I didn't want to grade papers and prepare a classroom and write lesson plans. "You'd make a great teacher, just like your mom." Nope. Not doing it.

I went to college with the intent of becoming a science writer. I was a chemistry major on the B.A. track looking to take a lot of writing courses, and possibly double-major with journalism. My academic and research advisors convinced me that if I really wanted to talk about the science, I should learn more of it. So I switched to the B.S. track. And got into research. And fell in love with chemistry all over again.

Graduate school was not originally part of my plan. But after the B.S., it seemed like the logical next step. At that point I wanted a job in industry working on semiconducting materials. A PhD would help that, and I was told it would be much easier to take the "graduate school vow of poverty" before an industry job, rather than after. So I went to graduate school.

The questions about whether I was going to be a teacher then changed a bit. People still asked if I was going to teach, just like mom. But then I'd also get a few "Are you going to be a professor like your grandfather?" Nope. Not teaching. I'm going to be a scientist, not a teacher.

That lasted until about 10 seconds into my first teaching experience as a graduate TA. It turns out that I love teaching. That even when things are hard and crappy and it seems like I don't understand anything at all, I can walk into a classroom and feel alive.

There's a funny thing about being a scientist, though. Even though there's a lot of cultural pressure to be an academic, there's a heaping helping of disdain for anyone who actually wants to teach. You're "supposed" to put research first. Many, many times I would talk to other scientists about future plans and lie right through my teeth. Of course I wanted to go the research path! Of course I wanted a future full of grant-writing and a massive lab of grad students and post-doc!

All I really wanted was a classroom full of curious undergrads and the chance to give them research experience.

This summer, at the Gordon Conference, I was surrounded by R1-types. And I, newly hired for a teaching position, was actually honest about my career goals. I said I wanted to teach undergrads and have the opportunity—but not the requirement—to do research. Some people gave me the "that's nice" dismissal. I had admitted that research was not my #1 Thing. It was like admitting some kind of weakness. Like I am "not a serious scientist" because I care about instruction.

I once had lunch with a seminar speaker who refuses to admit more than one undergrad in her lab at a time, yet seeks out graduate students who, like herself, had undergraduate research experience. She wants to take all of the benefit and share none of the burden. I find that incredibly unfair. But then, I would like to run the sort of lab that feeds graduate programs with experienced undergraduates. I suppose what I want is that burden without the same benefit.

So I plan to teach. And do research. But in that order and not the other way around. That doesn't make me a second-rate scientist. It makes me an educator.

At an institution of higher education, don't you think you need a few educators?

Excited state

My job has overwhelmed me more times than I can count. I have found it very hard. But I love it. So much. I must be nuts to love this much hard.

So far I’ve had students crying at me in the hallway and at office hours,1 one call to the paramedics, one student at office hours who proceeded to break one of my pens despite several requests to leave it alone, some angry demands for exam points back, some shy requests for office hour help, and many very funny emails.2 I’ve been called Professor a lot, Dr. Haas most of the time, and occasionally mistaken for a student. I’ve been consulted on a medical issue3 and I’ve been thanked for the tiniest things as if I’d bestowed some royal favor.

I’m primarily responsible for a lecture section, but I have to admit that my favorite time is spent in office hours and lab. I love lab. I get to wander through the room, nudging students into understanding. Why did that happen? Did you expect that? What does that mean? Last week’s lab was on light absorption and emission. I stationed myself at the absorption experiment (look at salt solutions with a spectroscope) and peppered the students with questions. Is this absorption, emission, or something else? How do you know?

Last Wednesday, I was going through this with one group, and a young woman got just to the edge of an epiphany—and she started to move. She was practically dancing, moving in place and gesturing as she talked. I could see her eyes light up, and her voice rose as she worked through the questions I hoped would lead to her understanding.

In emission, the electrons are in an excited state and fall to a lower energy state, releasing a photon.

This young woman, shaking with energy, was a student in the excited state. On the verge of enlightenment. It was beautiful.

My Wednesdays are long days. I left home that day around 7 am and got home after 9 pm. And I was finishing an exam, and planning out the next week, and calming test anxieties. Long, long days. It’s hard.

But that dancing student, eyes alight, she made the day sparkle. This is why I love this job.

1: I swear they weren’t crying because of me! I don’t want to be the scary professor.

2: Sorry students, but you guys totally crack me up when you’re so very serious.

3: “What should I do about this weird growth?” “Um, take it to a medical doctor? I’m a chemist.”

Some things I've enjoyed recently

  • Type:Rider, a game about the history of typography. It's beautiful and fun.
  • This post at Wandering Scientist. I love the two quotes at the end.
  • This post at the Chronicle of Higher Education blog. I'm bothered whenever I hear someone preaching about the "real world" and how students aren't prepared for it. The "real" world is full of real people who should be treated with respect and kindness. We gain nothing by dismissing our students.
  • Forbidden Island, my new favorite puzzle (it's a digitized board game, but I've been playing the local multiplayer solo)
  • 2048, which has usurped sudoku as my go-to time-waster. (Thanks a lot, @chemjobber)
  • iThoughts, an iOS/Mac mind-mapping app I've used for a year or two that was recently updated with some nice improvements.
  • This post at Penny Arcade on the use and purpose of Twitter was amusing. I also worry at times that my tweets aren't "good enough." Plus, I have a soft spot for Austen references.
  • This Periodic Table by Compound Interest is pretty cool.
  • It's not nearly as recent as the rest of this list, but I've really been enjoying the Points of Significance column at Nature Methods, and the Points of View column before it. My statistics background is much weaker than I'd like, so it's nice to have a primer. Points of View is similarly helpful for tips on designing figures.

Teaching Tips from Seminar

Teaching Tips from Seminar

I've learned that scientists, as a group, give pretty crappy talks. They love data and want to show you all the bits and pieces, even if there's really not time for that. They tell you things they have been working on so long and in such detail that they have forgotten what it's like to be their audience. They just dump information onto the digital page and expect you'll understand it. Instead of understanding in an instant, the audience is bombarded with new information that they need to process very rapidly before the next slide comes up with yet another information dump. This makes seminar a gamble. You spend an hour or more sitting in a dark room hoping to hear something interesting and knowing there is a possibility the best thing you'll get is a lukewarm cup of tea.

Friday's biophysics seminar was presented by Peter Chien of U Mass Amherst. He told us about recent work in his group that completes an 8-year story: they have been chasing down a mechanism for how certain proteins are broken down in Caulobacter crescentus bacteria.

It was excellent.

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Graduation Ahead

Today I had (most of) my pre-defense data meeting.1 My committee has declared me ready to write my thesis, and on track for graduation by or before August of next year. I'd like to be done by May, but that means t's crossed, i's dotted and revisions revised by April, and I still have another project to complete by then. Summer will get here soon enough.

I am glad to have an end in sight. I don't want to be a grad student forever, and some days it feels like it's already been forever since I started.

1: One committee member had to reschedule, so I get to give the same talk all over again tomorrow. I don't mind it a bit, though, because I always enjoy our meetings; I learn something new from him every time.

GoldiBlox and the Trouble with Pink

GoldiBlox are filling up my Facebook feed and my Twitter stream this week, despite the fact that I don't know any girls (or parents of girls) in the right age range for the toy. My thoughts on GoldiBlox haven't changed much since the Kickstarter campaign. The short version is this: an engineering toy marketed to girls is a great idea, but why must it be pink? 

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