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It is well known that I had a rough first year of college. I initially started this blog long ago to help me study towards bettering my grades. Well, since then I have switched majors (Microbiology, ftw) and have found myself in a very happy internship.

Regardless, I still find myself trying to come to ease with college in a hurry (two years down, one to go). There isn’t alot of help out there for science majors who struggle to balance everything that is important to them in life. Unfortunately, we have to make a lot of cuts in order to make our dreams come true.

I am having to quit my DnD group of close to two years because I have found that despite my incredible efforts towards garnering an A in my most difficult courses, I still fell short and I think the extra time Saturday evening for review (which I did loyally every Saturday in high school after a day of play and relaxation) is what I really need back.

So, here’s to a new start on education and a restarted blog to go along with it.

What to expect to see:
Lessons on Microbiology, Chemistry and college in general
Tips for the GRE
Tips for Graduate School
Occasional rants

Here’s to a good semester of summer courses!
Cheers,
Kitty

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This past weekend, I had a rather full discussion with my boyfriend, Justin, about the rather gray line between chemistry and its adjacent fields (such as biology).  Recently, I acquired a job working in the medical buildings with a microbiology lab and have found myself at a loss of words in awe at how beautifully my education and past lab experiences will fit smoothly into my upcoming ones.  As we come flying hard and fast out of high school, our minds bewildered with the idea of adulthood, we often only glance at the possibilities before us with bemusement before diving headlong into majors, minors and the livelyhood that comes with the title “college student”.

Now that I sit happily in my last few semesters, I feel that “the earth is getting rather large in the window”, as my mom likes to quote to me from my favorite movie.  Today marks the last week of my time as a student working with an あるばと, or part-time job.  Next week, I shall blast forward into what will hopefully be the rest of my life.  That being as it may, I was considering how closely related all the mechanisms of science really are.

Membrane pump like this!  It should move too!Take, as Justin and I did, chemistry in relation to biology.  Truely, the focus is rather similar.  Some chemists (and especially biochemists, whom I feel stand directly on the line between the two fields and wave their hands like only a mad chemist could) study on the mechanisms that cause life to function.  An example could be: what chemical mechanism drives that ion pump in the cell’s membrane?  Some biologists, on the other hand, could look at that same ion pump and wonder what effect it has on the organism as a whole.

As chemists, we work with the building blocks of everything on earth.  The keys I’m typing with, the board my professor isHoly Shit!  Yep, that's Chemistry for you.  Big Booms.  Always. writing on, the chalk, my lab partner next to me.  All of these are made up of the chemicals that we, via definition, focus on.  I find this staggering.  There is so much I could do and see, learn and discover but only so many years in which to do so.  It is rather unfortunate and yet at least I know I shall always be employed!  Of course, my field is narrowed by a driven need to improve the human race and my love for medicinal chemistry.  (The internship I had a few years ago solidified that for me!)

I just find it phenomenal that each and every object about us all is made of tiny particles fluctuating with tiny bonds through minuscule electrons.

Anyways!  Since that was my second rant in a row, I promise to have a lesson of some sort ready for later this week.  Tune back in on Thursday for some good, ol’e fashioned, IUPAC organic nomenclature.  That’ll be fun, right?

Happy Chemistry,

The Alchemist Kitten

Greetings, fellow chemistry aficionados.

Kitty is tired...*sigh*First of all, I want to extend a sincere apology for my lack of updates over the past few weeks.  Last week was a “test-block” for me–in which all of my classes decided to dump tests on me within a 3 day radius.  Needless to say, I was rather swamped.  Following that, mother nature, aided via stress and supplemental hormones, decided to strike me this week.  So, I sit here today on this beautiful Autumn Friday, I figure I ought to give you all a glimpse into the Kitten’s mind.  Lots of things have been flowing there recently and I plan just to let them out.

This semester has me taking the organic laboratory over again because OU, great school as it is, has required me to take their lab–apparently, SMU’s lab was not sufficient.  Initially, I had no problem with this, fully intending to make the most of a nice lab and previous knowledge of the experiments to be run.  Unfortunately, I’ve been sorely dissapointed.

Not only does the organic chemistry lab lack in luster, it lacks in teaching ability as well.  Besides spending two 3-and-a-half hour periods in the lab with a TA (whom I actually love and who is just as fed up as I am), I have to take time on Tuesdays to return to school at 5pm in order to sit through a lecture class.  Right, not so bad, really?  Wrong.  Though I hear that the lab professor isn’t half-bad when actually teaching Organic, he has only half-a-clue of what’s going on in the actual labs.

How so?  Our first real lab included distilling two compounds from each other using a Hickman still.  Ah, no biggie.  Distillations are easy, I thought, rather naively I might add.  The two compounds, had relative boiling temperatures of 90C and 120C respectively and thusly one can heat the compounds up to about 90, let it reflux until a reasonable amount of distillate forms, collect, then continue to heat up to 120 to collect the next sample.  Well, lo and behold, here I sit with my hotplate at 90C and nothing is happening.  Okay, I think. Maybe I should let it go for ten minutes or so.  It will boil.

Nope.  Never refluxed at 90C.  So, shrugging my shoulders, I cranked my hotplate up to 120C.  Again, I waited ten minutes.  No reflux.  Sighing with disdain, I crank the plate up even further and finally, the compounds begin to reflux at 150C.  Please, dear readers, note that I was using toluene, which should be on FIRE at this point in time.  (Okay, maybe not fire, but it should be burnt and crispy at this temperature.)  Incredibly frustrated as I was, I collected my distillates and submitted them.

My spectra came back the following lab period and specifically read two unknown chemicals that were NOT what we were supposed to be using.  So, not only did this lab fail incredibly, the manual or the prep-man in the chem stock room royally fucked up.  I am frustrated with this lab.  Very, very frustrated.

But, what can you do?  Unfortunately, I have no control over anything that happens in the lab (thankfully, that will change one Damn, I've never been so proud of ethanol!day).  I, like many of my fellow chemists in the lab, have to persevere through this bullshit for the rest of the semester.  Thankfully, not all is lost, as I have found that if I tweak the labs to make them more like SMU’s effective labs, I tend to get better results.  A prime example is my partner, Russ, and I’s perfect 95% Ethanol distillation and purification.  We’re quite proud of that moonshine! xP

This weekend looks to be full as I need to analyze and complete two long labs that I have done recently.  I’ll post more about my incredible disappointment with this lab as time moves on.  Hopefully, these complaints will bring clarity to my own work and perhaps to yours.

Cheers!

The Alchemist Kitten

(note: to see image captions, place mouse on image!)

Happy late update!  My week became something along the lines of “fucked” and so unfortunately, I am writing this during my D&D session.

So, today I shall be teaching a lesson on ionic bonding.  It is the most commonly known style of bonding and probably the most important style of bonding to baby-chem students who are studying solubility and other various aspects of compounds in solution.  (Both topics that I shall talk on at some point in time.)

Ionic bonds typically couple a metal from the right side of the periodic table to a non-metal to the left side of the periodic table.*  Since the right-side elements (such as Na, Li and K) typically have outer shells with either one or two electrons, they are much more capable of ionizing down to their cationic state.  Due to this property, a much more electronegative element (such as Cl, O or Br) can come right along and pluck off the “loosely” held electrons for themselves. (It should be noted that non-metals are usually greedy little bitches.  If someone lost an electron, it likely went to them.)

Now, this leaves us with a cation and an anion, which, as anyone who has ever played with a magnet would know, attract each other.  Thusly, we have an ionic bond.  It’s easiest to understand the ionic bond as occurring when opposite attract, but technically there is another force at play–energy. (It should also be noted that usually, energy plays a huge role in anything chemistry related).

I really gotta get a tablet...

I really gotta get a tablet...

Let’s use table salt as an example, seeing as it is the most commonly demonstrated ionic compound.  Energetically, it is more favorable for Na to lose its valence electron to Cl.  On the flip side, it is also favorable for Cl to pick up the extra electron.  Once this electron trade is done, both Na and Cl have fully filled valence electron shells. (Remember, all atoms are looking for a full eight electrons to fill their shells.  Except for H and He of course.)  Thusly, the bonding of the two atoms into a molecule produces a decrease in energy that is thermodynamically favorable.**

Since the bond is mainly a connection due to the polarized atoms, the Na region of the molecule is partially positive (little delta +) and the Cl region of the molecule, obviously, is partially negative (little delta -).  This effect makes ionic compounds break down easily in water, which is also ionic (with the H being + and the O being -).  With the ionic compound broken into its cation and anion, it is quite easy to add another compound (ionic or no) and induce a chemical reaction.  This is one of the prime reasons that ionic bonding is important to solubility rules.***

*It should be noted now that many of the common anions that baby-chemistry typically memorizes can also participate in ionic bonding and will often do so.  (Such as NO3-, which commonly bonds with Na to create an incredibly un-reactive compound that once drove me incredibly mad.  Due to its inert nature, it also is a commonly used salt-bridge in electro-voltaic cells–we use this for oxidation-reduction reactions and one will likely encounter them in all introductory chemistry levels.)

Hopefully this has made the idea of Ionic bonding a little bit clearer!

Happy Chemistry,

The Alchemist Kitten

**This concept is easily explained by the Gibbs Free Energy Equation.  It is an incredibly important topic to cover, and I shall do so once I talk of…

***Solubility rules, which is what I plan to teach on next, since I have covered-albeit briefly-ionization in water.

You guys have my sincerest apologies for my lack-of-update on Thursday!  I completely forgot!  However, as a treat, I decided to explain one of the more complicated concepts from general chemistry…

That’s right!  Today we’re going to talk about the seemingly complex topic of electronegativity.  A lot of general chemistry and baby/AP chemistry students struggle with this concept and how it applies to reactions and molecules.  For now, I’ll cover the general basics and trends of the subject.

First, let’s define electronegativity.

An atom is considered “electronegative” depending on its ability to attract electrons towards itself.  In this sense, electronegativity is a chemical property of a particular element.  Unfortunately, like most subjects in chemistry, this simple explanation, though sufficient, doesn’t completely grasp the entire subject.  For now, we will stick with this simple definition for our purposes today.

Since electronegativity is a chemical property, we should be able to map its trend across the periodic table.  Indeed we can.  Let’s think about some atoms for a moment and deduce whether they would prefer to have electrons or not.

Lithium—Li has three electrons in two valence shells.  Two electrons are on the inner shell closest to the nucleus and the last one is on the next shell alone and unpaired.  With this idea in our heads, lets ponder whether Li would want another electron or not.  The outer shell of Li requires seven more electrons to make the atom “happy”.  Finding seven electrons could be quite an impossible feat, and thusly Li tends to lose that electron rather than keep it.  This means that according to our definition of electronegativity, Li has low eNeg.

Oxygen—O has eight electrons in two valence shells.  Unlike Li, O’s outer shell electrons fill six of the eight electrons needed to fill up the second shell.  Again, let’s consider O ability to pick up electrons.  Those six outer electrons are not going to go away easily and thusly it is much more energetically favorable for O to pick up two extra electrons than to give away six.  Therefore, O has a high eNeg.

From looking at Li and O, we can define a trend of increasing eNeg going from left to right across the periodic table.  We’re not done yet, however!  Does the trend go up or down on the table?

Well, to describe this, we must think about atom size.  Let’s compare two right-side elements, say, F and I, both having a similar eNeg.  Comparatively, F is incredibly small—I having 44 more electrons than F—and therefore I’s outer seven electrons are much further away from the positive nucleus than F’s.  Due to this distance from the nucleus, I is less capable of attracting electrons than F.

So, our trend must increase in eNeg from left to right and from bottom to top! (A good way to remember this is “Up and to the Right”.)

Paint ftw!  I've got to get a tablet...

Paint ftw! I've got to get a tablet...

Hopefully, this little explanation helps you all understand the basic idea of eNeg and how to identify which atoms are more electronegative than others.

Happy Chemistry!

The Alchemist Kitten