PART I OF VI
A WORTHY CAUSE INDEED
by David Ng
GRIZZLY BEARS TAKE NORTHERN VACATION
by Bethany Lindsay
SCIENCE GETS ITS FIRST SUPERMODEL
by David Secko
WHAT IS BIOINFORMATICS?
by Joanne Fox
PATENTS AND INNOVATIONS IN BIOTECHNOLOGY: FROM A SATELLITE LOOKING DOWN AT OUR USE OF PATENTS IN THE GREAT PLANETARY SCHEME OF THINGS
by Azar Mehrabadi
ELSEWHERE AND OVERHEARD
by Caitlin Dowling
| || || ||A DIALOGUE WITH SARAH, AGED 3: IN WHICH IT IS SHOWN THAT IF YOUR DAD IS A CHEMISTRY PROFESSOR, ASKING WHY CAN BE DANGEROUS |
by W. Stephen McNeil
SARAH: Daddy, were you in the shower?
DAD: Yes, I was in the shower.
DAD: I was dirty. The shower gets me clean.
DAD: Why does the shower get me clean?
DAD: Because the water washes the dirt away when I use soap.
DAD: Why do I use soap?
DAD: Because the soap grabs the dirt and lets the water wash it off.
DAD: Why does the soap grab the dirt?
DAD: Because soap is a surfactant.
DAD: Why is soap a surfactant?
DAD: That is an EXCELLENT question. Soap is a surfactant because it forms water-soluble micelles that trap the otherwise insoluble dirt and oil particles.
DAD: Why does soap form micelles?
DAD: Soap molecules are long chains with a polar, hydrophilic head and a non-polar, hydrophobic tail. Can you say 'hydrophilic'?
DAD: And can you say 'hydrophobic'?
DAD: Excellent! The word 'hydrophobic' means that it avoids water.
DAD: Why does it mean that?
DAD: It's Greek! 'Hydro' means water and 'phobic' means 'fear of'. 'Phobos' is fear. So 'hydrophobic' means 'afraid of water'.
SARAH: Like a monster?
DAD: You mean, like being afraid of a monster?
DAD: A scary monster, sure. If you were afraid of a monster, a Greek person would say you were gorgophobic.
SARAH: (rolling her eyes) I thought we were talking about soap.
DAD: We are talking about soap.
DAD: Why do the molecules have a hydrophilic head and a hydrophobic tail?
DAD: Because the C-O bonds in the head are highly polar, and the C-H bonds in the tail are effectively non-polar.
DAD: Because while carbon and hydrogen have almost the same electronegativity, oxygen is far more electronegative, thereby polarizing the C-O bonds.
DAD: Why is oxygen more electronegative than carbon and hydrogen?
DAD: That's complicated. There are different answers to that question, depending on whether you're talking about the Pauling or Mulliken electronegativity scales. The Pauling scale is based on homo- versus heteronuclear bond strength differences, while the Mulliken scale is based on the atomic properties of electron affinity and ionization energy. But it really all comes down to effective nuclear charge. The valence electrons in an oxygen atom have a lower energy than those of a carbon atom, and electrons shared between them are held more tightly to the oxygen, because electrons in an oxygen atom experience a greater nuclear charge and therefore a stronger attraction to the atomic nucleus! Cool, huh?
SARAH: I don't get it.
DAD: That's OK. Neither do most of my students.
W. Stephen McNeil is an Assistant Professor of Chemistry at Okanagan University College in Kelowna, British Columbia. His lectures and conversation tend to incorporate a large degree of both gesticulation and pontification, occasionally of a frighteningly unbridled and reckless nature. He often reminds people of his namesake on "Blue's Clues", and he knows that already, so you really don't need to mention it again.
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archive (of stuff)
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notes (on masthead)
A DIALOGUE WITH SARAH, AGED 3: IN WHICH IT IS SHOWN THAT IF YOUR DAD IS A CHEMISTRY PROFESSOR, ASKING WHY CAN BE DANGEROUS
by W. Stephen McNeil
PHOTO FEATURE: A Photo of a Nice Set of Boobies We Saw at the Museum of Natural History.
by Christopher Monks
by Claire Salvador
THE BESTEST, MOST KICK ASS, HUMAN GENOME PROJECT
by David Ng
EINSTEIN AT PRINCETON
by Jonathan Cohen